Posts Tagged ‘Repco Brabham Engines’

(Ron Laymon)

Denny Hulme caresses his Repco Brabham ‘RB740’ V8 in the Mosport pits during the Canadian GP weekend, August 1967…

As well he should too, it was this engine which powered his Brabham BT24 to victory in that years drivers championship. Mind, you that statement is not entirely correct as Denny used the ’66 engine, ‘RB620’ early in the season as Jack raced the 740, that engine was only used by the Kiwi after Jack deemed it available and raceworthy to him.

In the meantime Denny scored 4th in South Africa and won at Monaco using RB620 V8’s- those results won Denny the title really, Jack was 6th and failed to finish in the same two races. Denny’s 51 points took the title from Jack’s 46 points and Jim Clark with 41.

Clark from Hill during the 1967 British Grand Prix at Silverstone, Lotus 49 one-two for a while at least, GH retired with engine failure on lap 64 to end a dismal weekend, he crashed after suspension failure on Saturday. Clark won from Hulme’s BT24 and Chris Amon’s Ferrari 312 (Sutton)

Clark’s 4 wins shaded Jack and Denny with two apiece in the epochal Lotus 49 Ford Cosworth. Any design which is competitive over four seasons, inclusive of drivers and manufacturers title wins (Hill in 1968 and Rindt in 1970) is ‘up there’ in the pantheon of great GP cars. The 49’s first win was Clark’s victory at Zandvoort in ’67 upon the cars debut, its last the result of Jochen Rindt’s stunning tiger drive at Monaco in 1970- at his friend Jack Brabham’s expense, the great Aussie pressured into a famous last lap error by the storming Austrian.

Without doubt the Lotus 49 was the car of 1967, its always said it would have won the title with more reliability that it did not have as a brand new car.

But that simple analysis fails to give credit to the Aussies.

The Brabham BT24 was a ‘brand-spankers’ design as well. Tauranac says that it was only his second ‘clean sheet’ GP design, his first was the BT3 Climax which raced from mid-1962. The GeePee Brabhams which followed were evolutions of that design.

Love these close-up shots. Its Denny’s BT24 and RB740 engine the cam cover of which has been removed to give us a better look. The cars spaceframe chassis is clear- small car for the era. Based on Tauranac’s BT23 F2 design the engine was tightly proportioned and economical of fuel so the package around could also be tight. From the bottom you can see the distinctive ribs of the 700 block below the top suspension radius rod. To its right is an ally tank held in place by a rubber bungy cord, a fuel collector which picks up from the two, one each side, fuel tanks. SOHC, 2 valve V8, circa 330 bhp in period. Cams chain driven. Note the rail carrying coolant behind and above the camshaft. Fuel injection is the ubiquitous, excellent Lucas product, to the left is the top of the Bosch twin-point distributor. In the centre of the Vee is a hornets nest of carefully fabricated exhausts- wonderful examples of tube bending art. Ferrari fitted 12 within the Vee of its engine in a trend common at the time. The idea was to get the pipes outta the breeze and away from suspension members. What a wonderful bit of kit it is (Laymon)

The ‘RB740’ SOHC, 2 valve, ‘between the Vee’ exhaust engine was also a new design. Both the Repco designed, Commonwealth Aircraft Corporation cast ‘700 Series’ block and the ’40 Series’ heads (the heads were cast by Kevin Drage at Clisby Industries in Adelaide) were new. They were completely different to RB620, albeit the 700 block could and was bolted to 20 Series heads and ancillaries when 620’s were rebuilt and its modified Oldsmobile F85 block cast aside as no longer fit for purpose.

Jack and Repco ‘blooded’ or tested the head design in the early 1967 Tasman races but the block was not ready then- the 2.5 litre 1967 Tasman engines were ‘640 Series’, a combination of the ’67 heads and the 1966 modified by Repco, Olds F85 blocks. The first 700 blocks were used in F1, not the Tasman Series. In fact the early ’67 F1 engines used by Jack were 640’s as well. Denny used 620’s early on in ’67, as mentioned above just to add to the confusion!

My point is that the all new Brabham BT24 Repco won 4 races and took the ’67 drivers and manufacturers titles beating the all new Lotus 49 Ford which also won 4 GP’s- Graham Hill was winless in the other 49 that year. (I’ve ignored the 49’s guest drivers in this analysis)

BT24 sans Hewland DG300 during the German GP weekend. Elegant simplicity of the design laid bare. Spaceframe chassis, rear suspension comprising single top link, inverted lower wishbone, coil spring/damper, twin radius rods and an adjustable roll bar. Eagle eyed Aussies may note the ‘Lukey Muffler’ tipped exhausts (unattributed)

It could also be said that the 49 chassis design was not really all new- the 1966 Lotus 43 is identical in layout inclusive of suspension and using the BRM H16 engine as a stressed member, as the Ford DFV was.

So whaddam I saying?

That the spaceframe Brabham BT24 Repco combination was ‘newer’ than the monocoque Lotus 49 Ford which was really the 43 chassis design, suitably lightened and modified to carry the DFV, a much lighter and fuel efficient moteur than the sensational but corpulent, complex BRM engine. Let the correspondence begin! Here is a link to my Lotus 43 BRM article, form a view yourselves.

https://primotipo.com/2015/02/17/jim-clark-taking-a-deep-breath-lotus-43-brm/

Tell me in a conceptual sense how the 49 chassis and suspension differs from the 43? There was plenty of Ford funded PR hoopla around the Lotus 49, we have all seen the footage. It was hardly going to be the case that Chapman said of the Lotus 49 chassis ‘we needed a known platform to bolt the new engine to, so we used the BRM engined 43 chassis design with minor mods to suit the much lighter, smaller DFV’. Much better to tout the whole lot as ‘all new’- no drama in that, its all fair in a corporate bullshit sense, its just not quite true and largely a myth perpetuated by many over time. Time after time!

Lotus were not the first to use the engine as a stressed part of the car either, although that is widely attributed to Chapman. Jano did it with the D50 Lancia, Ferrari with the 1512 and BRM the P83 H16.

In any event, lets give the Brabham BT24 Repco ‘740’ V8 the respect it deserves but seldom gets.

Clark in the Mosport paddock 1967, his eyes well focused on the fashionably attired young Canadian missy, despite having just bagged pole. Lotus 49 Ford (unattributed)

Canadian GP Mosport- 27 August 1967…

This first Canadian F1 GP was in many ways an exemplar of the words above. Clark and Hill qualified 1-2 with Denny sharing the front row on Q3.

Clark led from the start to be passed by Hulme, Denny’s flat, fat Repco torque curve was more suited to the slippery wet conditions than the DFV which was notoriously abrupt in its power delivery early in its development. Bruce McLaren’s BRM V12 engined M5A was up to 3rd at one point. As the track dried Clark worked his way into the lead- which he kept after rain started again until lap 68 when the engine cut out. Jack won from Denny with Hill in the other 49 4th and Canadian driver Eppie Wietzes a DNF during a Lotus 49 guest drive with the same ignition dramas as Clark.

Maybe the truth is that the difference between the Lotus 49 and Brabham BT24 in 1967 was that Clark sat aboard a Lotus not a Brabham? For sure Jimmy would have been lightning fast in the light, chuckable BT24. Faster than Jack and Denny for sure.

Graham Hill quizzing Jack about the pace of his BT20 ‘640’ at the Silverstone BRDC International trophy in April 1967, Mike Parkes Ferrari 312 took the win from Jack. Red car is Bruce McLaren’s McLaren M4B BRM (Schlegelmilch)

A further point is around car preparation. The 1962/68 World Champion, Hill G, still at the peak of his powers was effectively neutered from the time the 49 appeared by the unreliability of the chassis he drove- of his 9 Lotus 49 starts he retired 7 times. Three of those were engine failures, the others due to driveshaft, suspension, gearbox and clutch problems. Clark retired 3 times in the same 9 races with ignition, suspension and ZF tranny dramas.

Brabham Racing Organisation prepared beautifully consistent cars in 1967 powered by very reliable Repco engines. Factory Brabhams took the championship F1 startline 22 times in 1967 for 4 DNF’s, all due to 740 Series engine failures- Jack’s broken rod at Monaco, both drivers at Spa and Denny’s overheating at Monza.

Clark was far and away the quicker of the two Lotus men- Jim started from pole in 6 of those 9 races, Hill from pole in 3 of them. As I have said before ‘if yer aunty had balls she’d be yer uncle’- but IF Hill had won a race or two that Clark did not, the manufacturers title would have been Lotuses not Brabhams. Because the lads from Hethel did not prepare two equally reliable cars the title was Brabham’s not Lotus’, surely a fair outcome?!

Denny Hulme in his ‘brand spankers’ Brabham BT24 Repco ahead of Chris Amon’s Ferrari 312 during the 1967 French Grand Prix, Bugatti Circuit, Le Mans. Jack won from Denny, Chris retired on lap 47 with a throttle linkage problem. The Ferrari 312 was a big car, the sheer ‘economy’ of the little, light, BT23 F2 derived BT24 shown to good effect in this shot. Note the air-scoop used to cool the fuel metering unit in the Tasman and some of the ‘hot’ races in the GP season (unattributed)

Denny’s 1967…

Didn’t he have a ripper season! In addition to the F1 drivers title he could easily have won the Can Am Series in Bruce McLarens M6A Chev, the first of the wonderful ‘papaya’ cars too. He went back to Mosport a month after the Canadian GP and won the Can Am race in addition to wins at Road America and Bridgehampton. Bruce just won the title with a smidge more reliability than his Kiwi buddy, 30 points to 27.

Denny didn’t have great reliability in the Tasman Series at 1967’s outset but then again the Brabham main game was engine development in advance of the GP season’s commencement. The cars were match fit for the World Championship partially due to development work done in Australasia by Jack, Denny and Repco in January and February whilst Tauranac beavered away on his new BT24 chassis design back in the UK- which is about where we came in!

Michael Gasking in grey coat and Roy Billington in shirtsleeves fitting a 2.5 litre RB640 V8 at Repco Maidstone during the 1967 Tasman. Cars raced in the ’67 Tasman were BT22 ‘F1-1-64’ for Denny and BT23A ‘1’ for Jack. The latter car is very much the F1 ‘BT24 prototype’ being a modified F2 BT23 frame to which the RB640 engine was adapted. Not sure which car is being fettled in this photo. It looks as tho they are about to fire her up- you can just see the end of a white ‘Varley’ battery by Roy’s foot and a red slave battery alongside. The motors Bosch distributor cap is missing but not a big deal to fit. The sound of those engines is oh-so-sweet! Not sure who the other two dudes in shot are, intrigued to know (Gasking)

Who Says Ron Tauranac designed the Brabham BT24?…

The BRO lads based themselves at Repco’s Maidstone headquarters in Melbourne’s western suburbs during the Tasman Series to fit engines before the Kiwi rounds and before/between the Sandown and Longford rounds in Melbourne and Tasmania each year. These two events were traditionally the season enders.

During these trips Jack, Denny, Roy Billington and others out from the UK operated from Maidstone both preparing the cars and spending time with the guys who built their engines. The Repco fellas all have incredibly strong, happy memories of these times.

The sketch below was made by Jack and Denny in the Maidstone lunch-room during a break in the days proceedings on the ‘1967 tour’.

Michael Gasking recalls that in between tea and bikkies the ‘guys were explaining to us what the ’67 F1 car would look like and its key dimensions’- so there you have it, Jack and Denny’s conceptual thoughts on the ’67 F1 car! The funny thing is, at that time, early March 1967 Ron Tauranac may not have been too far advanced with the ’67 chassis, the first didn’t appear until Jack raced BT24/1 at Spa on 18 June.

In the interim Ron was busy at Motor Racing Developments pushing F2 Brabham BT23’s out the door- far more profitable work than knocking together a few F1 cars for Brabham racing Organisation!

In any event, what a wonderful historical document! JB’s rendering of the RB740 engine is sub-optimal mind you, but its clear the guys have taken the time to carefully draw the car in pencil, and then add the dimensions in ink, or ‘biro’ I should say!

(Gasking)

Its hard to compare all of the BT24’s publicly reported dimensions with Jack’s sketches level of detail but the total height of the car at 34 inches tallies, whereas Ron’s final wheelbase was 94 inches rather than Jack’s 91.5 inches.

Re-engineering Jacks total width from tyre to tyre outside extremities at the rear of 69 inches- to a rear track dimension, using his 12 inch wide tyres, gives a rear track calculation of 57 inches for Jack whereas Ron’s was 55 inches.

The little air-ducts either side of the nose and in front of the driver didn’t make it, the steering wheel diameter agrees at 13 inches mind you these were trending down to what became the 10 inch norm. The outboard suspension layout all around is spot on of course, as is the use of a V8 engine…

At the end of the lunch, Michael scooped up the drawing which is now, 50 years later shared with us, many thanks Michael! Wonderful this internet thingy, isn’t it?

(Max Millar)

Related Articles…

On the Repco RB740 engine

https://primotipo.com/2016/08/05/rb740-repcos-1967-f1-championship-winning-v8/

The 1967 Repco Brabham season

https://primotipo.com/2015/09/03/life-magazine-the-big-wheels-of-car-racing-brabham-and-hulme-30-october-1967/

Hulmes 1967

https://primotipo.com/2014/11/24/1967-hulme-stewart-and-clark-levin-new-zealand-tasman-and-beyond/

Tailpiece: 1967 wasn’t all plain sailing, Brabham, Monaco…

(Getty)

Jack looking intently at the sight of his RB740’s Laystall, steel crankshaft. He can see it thru the side of the engines block, an errant connecting rod has punched a hole in its aluminium casing! Dennis Jenkinson’s MotorSport Monaco ’67 race report records that JB started the weekend with an RB640 engine fitted, and popped a new 740 in- which had circa 20bhp more, which he ran-in on Saturday and then qualified with, on pole.

Bandini got the jump at the start with the rod failing on the journey to Mirabeau, whereupon Jack spun on his own oil, travelling backwards all the way to the Station Hairpin, in the middle of the jostling pack. But the robust engine continued to run on 7 cylinders for the journey back to the pits, where this photo was taken, the great Aussie inadvertently trailing oil all the way around the course, the lubricant having an easy path out of the moteur via a not insignificant hole!

The rod problem was quickly fixed by Repco who fitted Carrillo’s- drama solved. The chassis is BT19, Jack’s ’66 Championship winning frame. Brabham first raced a BT24 at Spa on 18 June, Denny did not get his until Le Mans on 2 July. So you might accurately say the ’67 drivers and manufacturers titles were won with a mix of 1966 and 1967 chassis’ and engines!

Bibliography…

 ‘Brabham, Ralt, Honda: The Ron Tauranac Story’ Mike Lawrence, GP Encyclopaedia, Michael Gasking, ‘History of The GP Car’ Doug Nye, Garry Simkin

Photo Credits…

 Ron Laymon, Michael Gasking Collection, Sutton, Getty Images, Max Millar

Postscript: Jochen Rindt driving the ring off the BT24 at Kyalami, South Africa on 1 January 1968- he was third behind a Clark, Hill Lotus 49 1-2. Clark’s last F1 win sadly…

 

 

 

 

 

John Surtees poses with his Ferrari 312, the Scuderia’s 3 litre V12 new season and new formula contender, March 1966…

‘Big John’ is probably feeling fairly confident at this point, Ferrari seemed to be as well prepared as they had been for the last formula change from 2.5 to 1.5 litres in 1961. They took the title convincingly of course, Phil Hill won it in the Carlo Chiti designed ‘Sharknose’ 156 V6.

Coventry Climax had withdrawn as an engine provider at the end of 1965, other than some transitional support of Team Lotus with a couple of 2 litre FWMV V8’s to tide them over. Generally, 1966 was a year of transition and therefore of opportunity for those who started the season with a fast, reliable package, the Ferrari seemed just that.

Click on this link for my article on the 1966 Grand Prix season;

https://primotipo.com/2014/11/13/winning-the-1966-world-f1-championships-rodways-repco-recollections-episode-3/

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‘Down Under’ Jack Brabham installed the first Oldsmobile F85 blocked Repco Brabham ‘RB620’ V8 into a year old Brabham chassis, BT19, built for the stillborn Coventry Climax Flat-16 engine and contested the Non-Championship South African GP at Kyalami in it on 1 January.

Repco then popped a 2.5 Tasman Formula RB620 V8 into BT19 for a couple of Tasman rounds, at Sandown Park and Longford, each time learning a little more about the engine and making it reliable.

Ferrari’s own 3 litre V12 was a trusty old warhorse which had served them well. It was a reliable Le Mans winning unit and more powerful than the Repco V8 but the car was heavy. Brabham’s BT19 was a light spaceframe and his 300 horses were stallions not geldings.

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The first GP of the new F1, the 1966 XV Gran Premio di Siracusa was on 1 April, Surtees won it in a 312 from teammate Bandini’s Ferrari Dino 246. The only other ‘new’ F1’s were the Cooper T81 Maserati’s of Jo Siffert and Guy Ligier both of which failed to finish. So too did Brabham’s BT19 with a Repco failure.

On 14 May the teams met at Silverstone for the XVIII BRDC International Trophy which Brabham won from Surtees and Bonnier’s Cooper T81 Maser.

Game on!

Off to Monaco for the first Championship round on 22 May, Jackie Stewart’s BRM P261 took the race from Hill’s P261 both cars with 2 litre versions of the old P56 V8 1.5 litre F1 engine, and Bandini’s Dino. Surtees and Brabham were out on laps 16 and 17 respectively with transmission dramas.

Bandini’s use of the Dino which as the teams #1 Surtees should have been allowed to race, in Johns assessment the better of the two cars for the unique demands of Monaco, was one of many dramas within the team which famously resulted in the headstrong Brit telling Ferrari to ‘shove it’ costing both a title which they may well have taken.

surtess 4

Surtees joined Cooper for the balance of ’66 and made the cars sing but Jack was away and running taking the title he and Repco deserved but which perhaps should have been Maranello’s not Melbourne’s…

Click here for an interesting article on Surtees;

https://primotipo.com/2014/11/30/john-surtees-world-champion-50-years-ago/

Ferrari 312 Specifications…

312 engine

The heart of any Ferrari is its engine of course, and what a glorious thing the Tipo 218 unit was.

Cast in aluminium alloy with cast iron wet cylinder liners, the 60 degree V12 had dual chain driven overhead camshafts per bank operating 2 valves per cylinder. The compression ratio was 11.8:1, heads incorporated 2 plugs per cylinder which were fired, old school, by a battery of 4 coils. The engine was dry sumped, the cylinders fed by Lucas indirect fuel injection. Claimed output was circa 360bhp at 10,000rpm, the reality probably a little less than that.

312 rear

The engine wasn’t really the cars weakness, it was probably more so the Tipo 589 chassis’s overall weight. Ferrari really didn’t get the hang of building a modern monocoque in the British idiom until they contracted John Thompson to build them one circa 1973!

Before then their tubs were sheet aluminium panels in a double wall riveted to a tubular steel structure. It was effective but heavy. The Ferrari’s suspension, as you can see is period typical; inboard at the front with a top rocker and lower wishbone and outboard at the rear with a single top link, inverted lower wishbone with forward facing radius rods for location. Uprights were cast magnesium with coil spring/shock units. Girling provided the disc brakes, which were inboard at the rear.

The Tipo 589 5 speed transaxle was sportscar derived, beefy and heavier than the DG300 Hewland box which became ‘de rigour’ in the Pommy cars of the era.

312 engine side

Shot above shows the beautiful standard of Ferrari fabrication and finish. Note the chassis, Lucas injection, twin-plug heads, alternator driven by the cams and wonderful exhausts which are fine examples of the pipe-benders art.

Credits: Popperfoto, GP Library, Reg Lancaster

Tailpiece: Why is that Simple Little Thing So Fast?…

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Enzo Ferrari ponders the 1966 consistent speed of Jack’s BT19 Repco at Monza on September 3 1966, the ‘Wonder From Down-Under’ beating the might of the Europeans…

What is he thinking I wonder? ‘why is it so fast, its last years spaceframe chassis, engine from someone i’ve never heard of in Australia and the block is an American Oldsmobile…’

In fact the following day was a good one for the Scuderia, Ludovico Scarfiotti’s 312 V12 took the win from Mike Parkes similar car with Denny Hulme’s Brabham BT20 Repco third.

 

 

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The Story of the Repco-Brabham V8 Racing Engine as conveyed in Repco Technical News Volume 12 No 2, November 1965…

This gem is from Michael Gasking’s Collection and is reproduced in all of its glory, this is the 1966 Tasman/F1 engine later more commonly referred to as ‘RB620’, its internal Repco Parts Co project code was ‘620’. It will be difficult to read on your ‘phone, a bit easier on a larger device!

We have covered this engine already in primotipo, click on the links at the end of the article for these stories. Just a couple of ‘editorial comments’ or observations.

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RB620 and F1…

No mention is made of the engines F1 application so late in the piece, the new 3 litre F1 began on 1 January 1966. Brabham and Repco were playing their cards, understandably, close to their chest. Remember the RB620 V8 first ran in a car at 3 litres not 2.5, at Goodwood before racing in the non-championship South African GP, at Kyalami on 1 January 1966.

Melbourne motoring journalist Chris de Fraga, well known and respected by generations of Victorian enthusiasts is credited with first reporting Repco’s F1 plans in the Melbourne ‘Age’ in early October 1965, a report denied by Repco at the time. This document dated November 1965 was presumably circulated in that month or the following one.

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Jack’s Lovechild…

Brabham’s parentage of the project is ignored in this largely technical treatise of the engine, Jack’s involvement not ‘front and centre’ in this public document given the need for F1 confidentiality.

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‘The Men’…

The duo credited with the engine in the brochure are Chief Engineer of the Repco Parts Group, Frank Hallam and Project Engineer Phil Irving, the only guy missing, as stated above is Brabham. Its worth musing for a bit about the roles these three men played in the championship winning RB620.

In simple terms Jack was the engines conceptual designer- he pitched the Repco board a simple engine using the F85 Olds block as a base whose completed dimensions were to fit the existing BT19 chassis. Phil designed it, inclusive of its drawings. Jack provided both conceptual design and practical feedback to Phil on regular visits to Irving who was based near Brabhams early in 1964 as he progressed the engines design. All of the ‘RB620’ drawings were done by Phil and signed by him according to ex-Repco engineer and Repco Historian, Nigel Tait who has seen and reviewed them all in the process of archiving them with RMIT University, Melbourne, in recent years. Hallam was Repco Brabham Engines Pty. Ltd. General Manager and Chief Engineer. His role was primarily a management one although he had engineering oversight, his direct design and engineering input into RB620 something Hallam has sought to grab a greater share of down the decades.

After Irving’s death, Hallam in his book ‘Mr Repco Brabham’ comprehensively dumps all over Irving and seeks to take more credit than he is due for the ‘RB620’ engine inclusive of positioning Irving as its ‘draftsman’ – ‘draftsman casual’ in the employee list in his books Appendix. In fact all of the ‘Drawing Office Personnel’ listed are described as ‘draftsman’ despite several being degree qualified engineers. Hallam, on the other hand, formally qualified as a motor mechanic, lists himself as General Manager/Chief Engineer. The positioning he inaccurately seeks to convey is clear. In that context its interesting to see Phil’s title as ‘Project Engineer’ in this Repco publication of the day.

The very well known F1 engine designer and manufacturer John Judd joined the Repco Brabham Engines Maidstone design team at Jack Brabham’s behest in 1966. He pretty much unwittingly walked into a storm in terms of the final breakdown in the progressively declining working relationship between Hallam and Irving. Judds arrival at Maidstone was unannounced by Frank to Phil, the design leader at the time, thereby lighting the fuse for a final confrontation which was becoming increasingly inevitable.

Judd got the ‘rounds of the kitchen’ from Phil when he joined RBE according to both Phil’s autobiography and Frank’s book but Judd has this to say about Irving’s contribution to ‘RB620’ in a recent ‘Vintage Racecar’ magazine interview;

‘When Jack returned (to the UK) from the (1966) Tasman  series, he asked if I could go to Melbourne almost immediately, and work with Repco designing parts toward the next year’s engine. That lasted for about four months and I was back again for six months in 1967 working on the 1968 4-cam engine.’

‘The original 1966 engine had been designed almost 100% by Phil Irving of Velocette and HRD fame with input from Jack and Ron Tauranac, but Phil didn’t fit in well with the Repco corporate structure and fell out with his boss Frank Hallam. My insertion into an already fragile situation led to Phil leaving after I had been there two months or so, and to his replacement by Norm Wilson. Looking back at Jack’s 1966 World Championship winning engine, I believe it was largely the product of one man, Phil Irving, to an extent that is and will remain unique.’

Don’t get me wrong, Hallam played a vastly important role in marshalling Repco corporate resources to assemble the men and modern machines to build World Championship winning engines in 1966 and 1967. He was also a wonderful foil between the demanding requirements of the Repco Board and the daily dramas in Maidstone of building and servicing racing V8 engines so far from Brabham Racing Organisation’s Guildford base. But his contribution is more management than engineering detail of RB620 when objectively looked at in the context of all the published evidence and the views of those there at the time.

The antipathy between Irving and Hallam was and is well known, few Repco people want to go ‘on record’ about the topic, which is both understandable and frustrating at the same time. They, rightfully, recognise the contributions of both men. Irving’s book is respectful of Hallam, Hallam’s of Irving not so and was published well after Phil’s death- the shit-canning of Irving is grubby and un-Australian really. If you are going to ‘have a crack’ do so when the other dude can defend himself. Hallam’s book was contracted by him from Simon Pinder, the author. It is not objective as such (neither is Irving’s autobiography of course) but does add much to fill in the RBE story, the long interview with ’67 RB740 designer Norman Wilson is gold for example,  but the books quality varies from gold to ‘merde’ depending upon the chapter. One needs quite a lot of Repco knowledge to pick the chapters to treasure and those to treat with rather more circumspection.

Nigel Tait told me that Jack Brabham was very angry with a fair bit of the contents of the book- it would have been a good idea for the great man to have read its contents before writing the publications foreword! I will explore the relationship between Irving and Hallam, and Hallam’s claims, in detail, soon. In short, this Repco corporate piece puffs up Hallam’s racing background and downplays Irving’s, ‘twould be interesting to know who ‘signed off’ the content of this document before it’s publication.

Enjoy ‘The Story of The Repco-Brabham V8 Racing Engine’, its sensational. Wish I had it when Rodway Wolfe and I tackled the articles linked below 2 years ago!, having said that we have included a good bit of granular stuff not included in this official publication, so read together are not a bad crack at the ‘RB620’ subject…

Etcetera: Repco RB620 articles…

On the engines design and build

https://primotipo.com/2014/08/07/rb620-v8-building-the-1966-world-championship-winning-engine-rodways-repco-recollections-episode-2/

On the successful 1966 F1 season

https://primotipo.com/2014/11/13/winning-the-1966-world-f1-championships-rodways-repco-recollections-episode-3/

Bibliography…

Repco, ‘Vintage Racecar’ magazine, ‘Mr Repco Brabham’ Simon Pinder

Credits…

Michael Gasking Collection

Tailpiece: Repco Brabham Boys, Longford, March 1966…

Phil Irving, with collar and tie chats to Brabham whilst Frank Hallam at right susses the Brabham BT19’s suspension. Not sure what Roy Billington is up to. Note the long inlet trumpets of the Tasman 2.5 RBE620 V8. Its the engines 3rd race, South African GP then Sandown Tasman the week before Longford. Jack was 3rd with overheating and low fuel, Jackie Stewart won in a BRM P261 from Graham Hill’s sister BRM. Its 6 or 7 March 1966. BT19 was Jack’s F1 championship winning 1966 car, still in Oz owned by Repco (oldracephotos.com/Harold Ellis)

 

 

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Introduction…

As Brabham, Tauranac and Denny Hulme scanned the competitive landscape as 1966 unfolded they formed the view that a similar formula to ’66 stood a good chance of success in 1967. A small, light, responsive chassis, this time designed around the engine. Remember that Jack’s successful ’66 mount, BT19 was an adapted, unraced 1965 GP car Tauranac designed around the stillborn Coventry Climax Flat-16. Ron’s ’67 BT24 was and is a superb car, its race record we shall review in an article about Brabham Racing Organisation’s (BRO) successful ’67 season.

In terms of the engine, keeping it simple and light had paid big dividends for Repco Brabham Engines Pty. Ltd. (RBE) in the first year of the 3 litre formula.

The fortunes of Ferrari, BRM, its H-16 engine the antithesis of the Brabham Repco’s in terms of weight and complexity and the Maserati V12 were well covered in my article on the ’66 season. Dan Gurney’s Weslake V12 engine showed promise but reliability continued to be an issue. The Ford Cosworth DFV didn’t race until the Dutch GP in June 1967. Brabham’s needed more power of course, too much power is rarely an issue, but they figured they needed less power than most others on the grid. If Jack and Denny started the season with a reliable, just quick enough package BRO could retain their title as others sought to make what were ultimately potentially quicker, more sophisticated multi-cylinder, multi-cam cars reliable. Click here for my article on Jack’s successful 1966 season; https://primotipo.com/2014/11/13/winning-the-1966-world-f1-championships-rodways-repco-recollections-episode-3/

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The beautifully fast, light, forgiving championship winning Brabham BT24 Repco 740 ahead of Chris Amon’s Ferrari 312 at Le Mans during the ’67 French GP. Denny 2nd to Jacks winning sister car, Amon DNF with throttle linkage failure (Automobile Year)

They were an intensely pragmatic group of racers in this Brabham/Repco senior mix…

Repco’s Charlie Dean, Phil Irving, Norman Wilson (designer of the ’67 RBE740 Series V8) Brabham and Tauranac all built winning cars (and bikes in Phil’s case) themselves, as in built with their own hands. Dean created the extraordinary series of Maybach Grand Prix cars, look at my Stan Jones article for much detail about this series of racers built by Charlie and initially raced by him, and then later by Stanley with much success. Norman Wilson built a Holden engined special in his youth covered in brief at the end of this article. Tauranac and his brother Austin built and raced the ‘original’ Ralts before Ron joined Jack in the UK in 1961.

Dean, Wilson, Tauranac and Brabham had been/were drivers. They knew what it took to win races. They understood winning was as much about torque as power. Handling was essential, the circuits then were all far from just requiring top end power, what was needed at Monza was different to the blend of corners and contours at Brands. All had driven cars and lost races due to unreliability. They understood a balanced package was critical, that whatever power they had needed to be put to the road. The point I make is that these guys were practitioners not theorists on ‘an engineering jolly’.

The RB group were about the application of sound pragmatic engineering practice, they didn’t have to think deeply about this stuff it was part of their DNA given the ‘build and develop it yourself’ school from whence they came. These guys weren’t ‘university engineers’ (which is not to say they lacked formal qualifications) but very practical chaps. Let the others chase ‘engineering perfection’ as they saw it, ‘an evolution of what we have is probably enough to do the trick’ was the correct thinking.

It was a whole different ballgame they confronted at the same time in ’68, but this was mid-’66, the game-changing DFV was still a distance away…

rb 740

Repco studio shot of the front of the amazingly compact ’67 championship winning ‘RBE740’, SOHC, 2 valve ‘between the Vee exhaust’, circa 330bhp V8. The ‘mix and match’ of engine parts described in the text is proven by use of 620 water pump, 630 chain timing cover, oil filter American ‘Purolator’, note oil pump below the dry sump pan, and up top the ends of aluminium water cooling rails, Bosch distributor and Lucas fuel injection trumpets (Tait/Repco)

1967 Engine Design Deliberations…

Ex RBE Engineer Nigel Tait; ‘By July 1966 the World Titles had already been ‘wrapped up’ for the year so the team were already thinking about the engine for 1967. Phil, Jack and Ron were all keen on the idea of getting the exhausts out of the airstream to clean up the car in terms of better aerodynamics and also for ease of plumbing the exhausts which otherwise had to negotiate the tubular chassis frame’. The 1966 BT19 championship winning chassis did not present a very effective frontal profile, its exhausts well out in the breeze.

Colin Chapman was far from the first chassis man to be prescriptive about design elements of an engine, as he was to Keith Duckworth in relation to the Ford Cosworth DFV, particularly in relation its integration with ‘his’ chassis.

Between the Vee exhausts had been raced successfully by BRM with its P56 1.5-2 litre family of V8’s in recent years. Ferrari also chose the same approach with its ’67 3 valve V12, its fair to say it was an F1 design trend of the time. In some ways Ferrari’s approach was better than Brabham’s as Ron maintained outboard springs and shocks on both the front and back of his ’67 BT24 chassis. Ferrari, as they did in 1966, used a top rocker and inboard front spring/shock presenting less resistance to the air at the front of the car at least. Ferrari went outboard at the back like Brabham. (and the rest of the grid)

rb 620 and 740

Old and new; ’66 RB620 305 bhp V8 left and ’67 RB740 330 bhp V8 right, F1 champions both. 740 was 3 inches shorter, 4 inches wider across the heads and 15 lbs lighter than 620. Dimensions otherwise the same; 25.5 inches long, 17.25 inches wide across the bellhousing (Repco)

Conceptual Design of the Heads…

RBE Chief Engineer Norman Wilson; ‘ It would have been Jack’s idea to put the exhausts in the centre (of the Vee). Jack asked if it could be done. I remember when i started designing them i spent a lot of time, probably 3 or 4 days, just drawing one cylinder up to try and prove that you could fit everything in. See you have got a whole row of head studs, you have got to have water passages between the port. The whole idea was to prove that you could get the inlet port in, exhaust port and all the head studs. That was a giant task to figure out in a way’.

‘It meant putting the outer row of studs underneath the exhaust ports. I don’t think i have the layout now but i remember spending a huge amount of time and finally i went to Frank Hallam (RBE General Manager) and said i think we can do it. And thats how the 40 Series heads started’. ‘To manage to get everything on one side and the thing is unlike most engines we built as we wanted big ports. So to fit all these big ports in plus the port wall, plus the bolt bosses was a major task. I think it took about three days work for me to fit everything in a rough layout’.

jack butt

Jack’s BT24 Repco 740 being fettled during ’67, circuit unknown. ‘Box is 5 speed Hewland DG300 transaxle, note rubber ‘donuts’, Lucas injection ‘bomb’ or fuel pump to the right of the box, also rear spaceframe chassis diaphragm. Getting the exhausts outta the airstream shown to good effect in this shot (unattributed)

The ’40 Series’ Between the Vee 1967 Cylinder Heads Design Detail…

‘…the new cylinder heads retained parallel valves but they were now in line with the cylinder axis (instead of at 10 degrees to the axis as on the ’66 20 Series heads and were flush to the head face’ said Wilson. ‘The 40 Series heads used the Heron head design. In this design the cylinder head is flat and the piston has the combustion chamber in the top of the piston (a bowl in piston arrangement). The other feature of the 40 Series head is that it had a tall inlet port. It had a fairly long, relatively straight section there on Jack Brabham’s suggestion. He had received some highly secret information from Honda that this was the way to go. In hindsight i don’t think so. All these things are better in hindsight, but that’s how we did it’

‘The Heron head, i think everyone agreed, had to be the way to go because the Cosworth SCA (F2 engine) was 1000cc and was putting out 120bhp. At the time in F2 it was winning everything. I think it put out 123bhp. Now if you are looking at a 3 litre engine, thats 369bhp. And at that time that would have been been looking for us a fairly exciting sort of figure. The other point about the Heron head is it allowed us to have a single camshaft which we wanted to have the low weight, simplicity and ease of manufacture’.

‘The 40 Series head was purely made for the car. No other reason. It put the exhausts down the centre of the Vee…thats what Ron wanted, he made the car so why not get what he wanted’.

‘The highest output of the 740 Series 3 litre was only a bit over 330bhp. This horsepower rivalry between the different engine manufacturers at the time, the horsepower numbers were really irrelevant. At the time Maserati claimed about 500bhp, but they were adding on about 100bhp to make up for the exhaust gas pollution in the test cell. But really its about the area of horsepower curve’. ‘If they had 500bhp they would be leaving us behind a lot quicker than they are leaving us behind!’ was a quip Rod Wolfe recalls Jack making to the boys in the RBE engine assembly area on one of his trips to Australia in 1967.

‘One of the philosophies was for the engine to always have a wide power range and good power at the bottom end of it which suited the light car. So if ours was 330bhp there was no way other cars had 400-500bhp claimed. Our power was distributed much more evenly across a wider range of revs. Thus Denny Hulme would say it was great to drive a Repco Brabham because he could overtake competitors in the corners as if they were ‘tied to a fence’.

There were some problems with 40 Series head porosity during ’67 as ex-RBE machinist/storeman Rodway Wolfe recalls; ‘Norm did a fantastic job to even succeed with the casting and it proved to be a great engine in larger capacity too, bigger valves etc…we were able to fit very large valves without too many seat problems. The 40 series did have a lot of porosity problems with the ports, some we scrapped as the ports actually broke through when we were porting them and there was not the welding equipment available that we have nowadays to repair them. Porosity, a big drama, as i say, one of my jobs was to send the castings to ‘Nilsens Sintered Products’ in Richmond where they placed the heads in a vacuum and impregnated them with hot resin. Vacuum impregnation solved some of these problems’.

jack wf

Brabham on the Warwick Farm grid, WF Tasman round in 1967. In relation to the cooling duct feeding the engine Rodway Wolfe comments ‘There were a few heat problems in the valley of the engine with the 40 series as the fuel metering unit was also located in the valley but small heat shields seemed to correct this problem and it was not an issue once the car was on the track of course’. It seems these ducts were used in the ’67 Tasman rounds on the 640 engines used by Jack and Denny and subsequently sporadically on the 740 engines, Le Mans for example (Bruce Wells)

A typically pragmatic decision to the heads was made in relation to the 1967 Repco block…

Remember that the ’66 engine used a heavily adapted version of the Oldsmobile F85 aluminium block. Repco still had a swag of unused blocks sitting in Rod Wolfe’s Repco store at Maidstone. The blocks had been successful, a world title proof enough of their effectiveness, but the machining and adaption required to make them an effective race tool meant they were expensive but still sub-optimal. But it wasn’t all plain sailing with the block however much it may have seemed so from the outside, Tait; ‘For much of 1966 we had serious blowby issues due to distortion of the dry sleeves and it was not until almost the end of that year that we went to wet sleeves. The F85 Olds blocks came with dry sleeves in situ’.

Repco’s race engine commercial ends were to be served by building and selling engines for Tasman use and for Group Seven sportscars, burgeoning at the time globally; 2.5 litres was the Tasman Formula capacity limit, the F85 ‘maxxed out’ at 4.4 litres which was the capacity used for the sportscar engines. Repco’s first sale of a customer engine was the 4.4 litre 620 Series unit sold to Bob Jane for his Elfin 400.

So Repco decided to ‘have their cake and eat it too’. The new bespoke ‘700 Series’ block would allow all of the F85 ‘600 Series’ bits and bobs to attach to it; heads, timing case, sump the lot. So Repco could gradually use its stock of F85 blocks for Tasman and sportscar use whilst ‘700 Series’ blocks were used in F1 for 1967 and more broadly in capacities up to 5 litres subsequently. As engines were rebuilt the 600 blocks were replaced progressively by 700 series units, 600 blocks ceased to be used when there were none left. Typically practical, sensible and parsimonious Repco!

Whilst the ‘700 Series’ block design decision, to allow 600 hardware to be attached was a ‘functional’ pragmatic decision the aluminium block itself was also improved being redesigned to increase rigidity. The new block design was commenced by Irving, he and others say, prior to his departure from RBE, but the completed block is his replacement as Chief Design Engineer, Norman Wilson’s design.

rb team

The post Phil Irving RBE design team; L>R GM Frank Hallam and Engineers Norman Wilson, Lindsay Hooper, John Judd and Brian Heard (Repco)

Phil Irving’s departure by resignation or sacking by RBE GM Frank Hallam is an important part of the RBE story and will be dealt with in a separate article. I explore not just the difficult relationship between these two characters but also the broader issues of the leadership of Repco, CEO Charles McGrath’s key enduring support of the RBE program and the appointment of Bob Brown as the Director responsible for RBE instead of alternatives including Charlie Dean at the projects outset. The antipathy between Hallam and Irving was partially about personality but also about politics and legacy in terms of who is responsible for what of the RB620 design and build. More on this topic very soon.

For now lets just focus on the RB740 engine which in no way shape nor form was negatively impacted by Irving’s departure…whilst noting that their probably would have been no 740 had it not been for the success of Jack and Phil’s RB620, JB as the engines conceptual designer and PI as its detail designer and draftsman…

block

Machining the RB700 block, note the stiffening ribs referred to in the text (Wolfe/Repco)

Norman Wilson; ‘When i went there (to RBE from Repco Research) John Judd (who had been seconded to Repco by BRO in the UK) had done a new crankcase. So i asked to look at it and John showed it to me and i said we can’t make it. It was impossible because it was the basis of a whole new engine. It became a mutual decision (by the design team) that we make a crankcase that went underneath, on top of and behind exactly what we had’. ‘We couldn’t have made a crankcase, head and timing case all at once. So we made a crankcase and then we did the 40 series heads. We had to have a timing case with the heads but it meant we didn’t have too much to do at once and we just kept progressing’.

Wilson;’The new crankcase was designed from scratch but was also designed so it could accommodate the 20 series cylinder head if we wanted to. It was critical being a fairly small outfit that we had the maximum amount of interchangeable flexibility between all the components that we made. So the 700 series crankcase was designed to overcome the problems that we had seen or experienced with the Oldsmobile F85 600 series crankcase. It had wet liners, that in part was due to the fact that it was easier to cast the cylinder block with a wet liner design in that it simplified dramatically the coring required for the casting of the block’.

‘The Oldsmobile engine showed it had main bearing problems so we altered the main bearing arrangement to be much more rigid. We extended the studs up through into the centre of the Vee with nuts on top to take some of the load up through to the top of the block. The unfortunate part of that was the design was right but people would always do the nuts in the top up tight. And of course what would happen was the cylinder block being aluminium would expand more than the stud and would eventually break it. What they should have done, and no one would listen, was do them up at a much lower torque so when the engine got hot it would put the right load on the stud’.

repco boys

RBE Boys, Maidstone, undated but circa 1966/7. Back L>R Kevin Davies, Eric Gaynor, Tony Chamberlain, Fred Rudd, John Mepstead, Peter Holinger. Middle; Vic Mosby, Howard Ring, Norman Bence. Front; David Nash, Rodway Wolfe, Don Butler (Tait/Repco)

‘The front bearing panel of the block was made stronger because this had proved to be a weakness with the Oldsmobile block. The back of the block was made with the same stud pattern as the Olds block so that all the existing gearbox adaptors could be used. The block was made with the idea of making it as light as possible and that was one of the critical things in design. In the end Frank suggested we put some diagonal ribbing on the 700 series crankcase walls to strengthen them’. ‘The sidewalls of the crankcase were actually bolted to the main bearing caps…cross bolting (and strengthened the crankcase considerably). So i felt the diagonal ribbing was really quite irrelevant. …Frank wanted it and, you know, he was a pretty good boss to work for, so thats what we did’.

‘The other thing about the block was that later when we made the 4.2 litre Indianapolis engines (760 Series DOHC, 4 valve V8 in 1968/9) we could alter the sealing arrangements, in fact the later F1 engines (’68 860 Series) were the same, so we used Cooper rings instead of head gaskets. Cooper rings sealed the combustion chamber and O rings sealed the water passages. But we also then had a groove around the outside of the Cooper ring joined with a shallow slot to the edge of the head so if one Cooper ring leaked slightly there was no way it would pressurise the cooling system’.

rb block

RBE700 Series block, note the cross bolted 5 main bearings (Repco)

‘With the Indianapolis engine (760 Series 4.2) those grooves came out of the inside of the Vee. So you could run your engine in the pits and you could put your finger over the end of each groove and you’d know if any of the Cooper rings were leaking slightly. The 700 block was the same height as the Olds F85 block. And the 800 block (860 F1 and 830 Tasman 2.5) was a (1.5 inches) lower one to make the engine smaller.’

The 700 Series block apart from being stronger was also 15 Kg lighter than the F85 ‘600 Series, Norman Wilson again; ‘The F85 block was designed to be diecast on a diecasting machine, it was perhaps a bit thicker in spots just to make it easier to cast. We got rid of a considerable amount of aluminium around each cylinder…The Repco block didn’t have all the bosses down the centre along the block for the cam-followers. It didn’t have the cam-bearings for the centre camshaft (of the F85) We didn’t have the stiffener plate on the bottom. The bearing caps were bigger but they were done a bit better and they were probably no heavier than what was there. And in all the places where strength was not required we just skinned them down as much as we could’.

brochure

(Wolfe/Repco)

Most of the components for the engine were made by Repco subsidiary, Russell Engineering, few were contracted out.

Wolfe; ‘Most of the RBE engine components were made at the Maidstone factory. The pistons and rings however were other Repco companies and the crankshafts Laystall in the UK but no other F1 engine constructor made their own pistons and rings in 1966, even Ferrari used Hepolite pistons so Repco were unique’.

Harold Clisby’s engineering business in South Australia cast many of the heads. Kevin Drage, the senior engineer at Castalloy, the Clisby subsidiary who made the heads recalled that around 120 cylinder heads of four types’ 30,40, 50 and 60 Series were cast by the company over the period of the RBE program.

The 30 Series head was detailed by John Judd and was two valve with inlet and exhaust ports on either side of the head, ‘crossflow’ inlets between the Vee and exhausts out the side. 40 Series (the ’67 championship winner) heads were detailed by Norman Wilson which had inlet and exhaust ports on the same side of the head, between the Vee exhausts.

Drage recalls that; The two valve 30 and 40 Series heads were soon followed by the four valve 50 and 60 series designs. John Judd drew these up with the 50 Series design having diagonally tangentially ported inlet and exhaust valves resulting in 16 inlet trumpets and 16 exhaust pipes, the 60 Series design having siamesed inlet and exhaust ports’. The 50 Series heads which were built and dyno tested and the 60 Series 1968 F1 4 valve, DOHC design are a subject of a future article. The fact that RBE persevered so long, at GM Frank Hallam’s insistence with the 50 Series heads delayed development of the 60 Series design, to RBE and BRO’s cost during the ’68 F1 season.

The Commonwealth Aircraft Corporation at Fishermens Bend, not too far from RBE’s Maidstone factory made the alloy crankcases and timing covers, note that Wilson went to double-row timing chains with RB740 compared with the single chain of RB620.

Ex-Repco engineer George Wade is often given credit for the camshafts but Rod Wolfe says; ‘we made the camshafts for all of the engines, George Wade profiled them to various specs but we turned the billets with a mimic tracer on our Tovalieri lathe. The very first 620 cams were cast iron but were changed to steel in 1966’.

Lucas fuel injection was of course again used, as well as a Bosch distributor.

Summary of RBE740 F1 3 litre engine specifications/suppliers…

Bore/Stroke; 3.5X2.55 inches, capacity 2996cc. Power 330bhp@ circa 8400rpm, weight 350 pounds

Compression ratio 12:1, valve sizes 1 13/16inches inlet /1 1/2 inches exhaust, valve angle vertical, valve lift .40. Valve timing 50, 70, 50, 70

Pistons, rings and main bearings by Repco, big end bearings supplied by Vandervell

Lucas fuel injection, Bosch coil and distributor, Champion plugs, Esso fuel and oil and Borg and Beck clutch

Denny Hulme and Jackie Stewart, Levin NZ Tasman 1967 (Digby Paape)

Denny Hulme DNF ignition and Jackie Stewart 2nd in their ‘between the Vee’ exhaust Brabham BT22 ‘640 Series’ Repco and BRM P261 respectively Levin, NZ 14 January 1967 (Digby Paape)

Racing the 640: 1967 Tasman Series…

The first race of the 1967 GP season was the South African GP at Kyalami on January 2, Jack and Denny raced 620 Series V8’s, the 740 was running late due to delays in patterns being made for the 700 crankcase. Its an interesting observation given that Hallam told Brabham by letter dated 23 September that the 700 patterns were half finished. In any event, the engine was late so made its debut in the Tasman Series, or more specifically 640 Series engines did; the new heads atop the 600 Series/F85 Olds blocks.

jack south africa

Brabham giving his 620 engined BT20 some welly at Kyalami during the South African GP at Kyalami on 2 January 1967, he was 6th from pole with Denny 4th from grid 2. Pedro Rodriguez won in a Cooper T81 Maserati (unattributed)

RBE staff numbers during the Christmas/New Year 1966/7 period swelled to 37, 23 engines being assembled during this period. Frank Hallam records that due to the great amount of dismantling, assembly and experimentation that took place only four 2.5 litre motors raced in the Tasman Series. The 640 series 2.5 litre Tasman engines gave circa 265bhp@8500rpm.

Brabham’s full ’67 F1 season i will cover in a separate article, here we look at the Tasman races for the 640 and early season F1 races of the 620 and 740.

gasking and bton, pre sandwon

RBE’s Michael Gasking and BRO’s Roy Billington and another mechanic prepare Brabham’s ‘RB640’ 2.5 V8 engined BT23A before the Sandown Tasman round on 26 February 1967, DNF ignition. Repco Maidstone factory (Wolfe)

If you take the view that the ’67 Tasman was a warm up for the ’67 World Championship then it was a success for Brabham and RBE. The 40 Series heads were thoroughly race tested during the annual Australasian summer contest.

Equally important was Jacks mount, his car designated BT23A was an adaptation of Ron Tauranac’s very successful new 1967/8 BT23 F2 design, which won dozens of races in Ford Cosworth FVA 1.6 litre F2 spec. The Tasman BT23A was effectively the prototype of the BT24 which went on to win the ’67 titles, so the Tasman ‘blooded’ both the chassis and engine well before the F1 season. The reliability which flowed from this development process won RBE and BRO the ’67 championships, the Lotus 49 Ford Cosworth DFV was well quicker but had not had the development miles the Brabham Repco’s had…

Jim Clark took the 1967 Tasman title in an F1 Lotus 33 fitted with a stretched to 2 litre Coventry Climax FWMV V8 engine, a quick, reliable, well proven combination. Clark took 3 wins, Jackie Stewart 2 in a similar F1 BRM P261. But the stretched to about 2.1 litres P56 V8 stressed the BRM transmission to its limits, the ‘tranny its weakness that summer. Jack was equal 3rd on the points table to JYS with 1 win.

Jim Clark, Lotus 33 Climax, NZ Tasman, Levin 1967

Jim Clark Lotus 33 Climax, Levin International winner, 14 January 1967 (Digby Paape)

Jack and Denny contested all rounds of the championship with the exception of Teretonga, the last Kiwi event. Jack took a win at Longford and Denny 3rd at Wigram his best. Brabham had a lot of unreliability but the problems weren’t in the main engines; for Denny a radiator hose at WF, gear selector at Sandown and electrical problems at Longford and for Jack a driveshaft breakage at Teretonga and ignition dramas at Sandown.

Denny Hulme, Brabham BT22 Repco, 1967 NZ Tasman, Levin

Denny Hulme’s pretty, effective, Brabham BT22 ‘640’ Repco, Levin 1967. DNF ignition (Digby Paape)

At that stage Repco hadn’t sold customer Tasman 2.5 engines of any type, the engines were made available later in the year in time for commencement of the domestic Gold Star series (640 & 740 Series 2.5 V8’s) in the meantime the more important business of getting the 3 litre ‘740 Series’ V8’s into Tauranac’s exquisite little BT24 was the priority.

jack and denny

Jack from Denny in BT20’s; Jack’s 740 engined and Denny’s 620, Denny won both heats and Jack the final giving the 740 the first of its many wins in 1967. Oulton Park ‘Spring Cup’, 15 April 1967 (Brian Watson)

The first F1 event of the European ’67 season was the Race of Champions at Brands Hatch on 12 March. Dan Gurney won both heats and the final in his Eagle T1G Weslake, Jack was 9th a ’66 spec 620 engined BT20 with Denny DNF, similarly equipped.

The ‘Daily Express Spring Cup’ at Oulton Park followed on 15 April, Brabham ‘cleaned up’ in BT20’s; Denny won both heats and Jack the final taking a great race win for the new 740 3 litre V8 with Denny 2nd in a 620 engined ’66 chassis.

jack monaco

Jack proved the speed of the new RB740 V8 at Monaco, its championship race debut, plonking it on pole but it went bang with a broken conrod in the races 1st lap, car is Jack’s beloved ‘old nail’ Brabham BT19, his ’66 championship winning chassis. Denny won in ‘last years’ quick and reliable BT20 Repco ‘620’ (unattributed)

BRO fitted its first 740 Series engine just in time for the Monaco GP on May 7. Apart from the delays caused by late patterns for the blocks, Repco Die and Tool Co forged conrods developed faults. After being unable to establish why the Repco rods were failing the team went the Carillo route, the team using these tried and true products…despite not being made in Oz! Rod Wolfe; ‘We did discover that the champfer at the bolt heads did not match the bolt radius under the head of the bolt and even when tensioned correctly they were not seating properly resulting in a couple of failures’.

The definitive RB ‘740 Series’ engined Brabham BT24 didn’t appear until Jack gave the chassis/engine combination its championship debut at the Belgian GP, Spa on June 18. This was 2 weeks after the Ford Cosworth DFV V8 took the first of 155 GP wins, the 1967 successful Brabham GP season a Repco story for next time…

denny spa

‘Black Jack’ at La Source during the ’67 Belgian GP. Both he and Denny retired with engine problems in BT24 and BT19 respectively. Dan Gurney took a famous and well deserved win in his Eagle T1G Weslake V12, 18 June. Compact nature of the F2 derived BT24 clear (unattributed)

Repco 1966/7 promotional film…

Check out this great footage, the first half covers Brabham’s victorious 1966 F1 season, the other bit the ’67 Tasman season, the debut of the 640 Series V8’s including some factory footage of the engines build.

Etcetera…

test house

Rodway Wolfe ‘The dyno test house at the rear of the Repco Maidstone factory. The silver drum on the side was the fuel tank which was changed when needed. The walls of the building were very thick…when the engines were running at full noise you could hold your hand against the wall and get a massage! Fascinating!’ (Wolfe)

jack wf

Repco 640 2.5 V8 power; Jack all cocked up in Warwick Farm’s Esses during the AGP, Warwick Farm 19 February 1967. Brabham was 4th in his BT23A, Stewart won from Clark and Frank Gardner in BRM P261, Lotus 33 Climax and Brabham BT16 Climax respectively (unattributed)

repco holden

Repco works Brabham Repcos’ on the move, Tasman Series, Longford, Tasmania 1967. ‘Rice Trailers’ the ducks guts at the time, tow cars are Holden ‘HR’ Panel Vans, 3 litre straight OHV 6 cylinder engines and ‘3 on the tree’ column shift manual ‘boxes (Ellis French)

jack sandown

Sandown Tasman, 26 February 1967, Brabham, Brabham BT23A Repco, Stewart BRM P261 and Hulme on the outside, Brabham BT22 Repco, all DNF! Jack with ignition, Stewart crown wheel and Hulme gear selection problems. Clark won in a Lotus 33 Climax. You can see the ducts directing cooling air between the Vee shown in an earlier shot (unattributed)

rcn

Jack hooks into the Viaduct ahead of Jim and Denny in David Chintock’s impression of the ’67 Longford Tasman round which Brabham’s BT23A won (Wolfe/Racing Car News)

Etcetera: Norman Wilson RBE740 Chief Designer…

rb norman

Norman Wilson in the study of his St Kilda, Melbourne bayside home in early 2016 (Greg Smith)

Its interesting context to Wilson’s work at Repco Brabham Engines to look at the car he built as a ‘youngster’ before his ‘glory years’ as part of the Maidstone team. The car is both innovative and practical in its adaptation of proprietary parts, a combination applied in his later work.

As the cars current owner Greg Smith observes ‘the Norman Wilson Special is a beautiful study of a late fifties racing car with its Mercedes’ styling and layover engine, side vents and knock-off wire wheels’

rb nw spl

‘Norman Wilson Spl’ in the foreground at Templestowe Hillclimb in then outer eastern Melbourne. Pat Hawthorne’s Lycoming Spl behind. The carbs are Webers, sidedraft right angle alloy castings (Greg Smith)

Norman started his 6 cylinder Holden engined ‘Norman Wilson Spl’ around 1956 aged 29/30. The chassis is a spaceframe, front suspension Wilson’s using inverted Holden uprights and wishbones, his own cross member and geometry. Steering is rack and pinion. The rear end is a ‘cut and shut’ Holden with an offset diff to lower the driver, springs are quarter elliptics with some neat locating links.

The clever bit was laying the Holden engine over at 30 degrees to the horizontal to both lower both the centre of gravity and bonnet line. By the time the car was finished Norman had moved to Repco, where it was completed and furnished with 3 large, single throat Webers Charlie Dean bought for Maybach but never fitted to it when that car was fuel injected. The ‘box was Jaguar, the beautiful aluminium body built by Barry Hudson who also did the Ian Mountain (Peugeot) Spl.

Norman raced the car, mainly in Victoria from 1960-63, it passed through several hands before being ‘chopped up’ in the late ‘60’s. With the interest in historic racing growing, and knowing the historic significance of the car and driver, reconstruction was commenced by Graemme Brown in Adelaide in the mid 1980’s, its first run in 1997. The car is currently being rebuilt by Victorian racer, engineer and raconteur Greg Smith to its precise period spec from whom this history and photos were provided. There is a whole lot more to this incredibly clever car built by Wilson in his youth, we will do a feature on it when Greg is close to its completion, I’ve seen it, the thing is sensational, Smithy will race it during 2017. I also plan to write more about Norman Wilson’s career, too little is known about this fella, now 91. so important in the Repco story.

Bibliography…

Recollections of Rodway Wolfe and Nigel Tait

Norman Wilson quotes from Simon Pinder’s ‘Mr Repco Brabham’, Doug Nye ‘History of The Grand Prix Car’, ‘Phil Irving: An Autobiography’

Kevin Drages comments from ‘The Nostalgia Forum’

Greg Smith’s photos and details of Norman Wilson and the ‘Norman Wilson Spl’

Photo Credits…

Rodway Wolfe and Nigel Tait Collections, Repco Ltd archive

Autocourse, Digby Paape, David Keep, Bruce Wells/The Roaring Season, David Keep/oldracephotos.com, Automobile Year, Ellis French, David Nash

Tailpiece: Jack Brabham guides his Brabham BT23A Repco into the Viaduct on his way to victory in the ‘South Pacific Trophy’, Longford 5 March 1967. He takes the first of many ’40 Series’ Repco 1967 wins…

jack longford

 

post

Jack Brabham, Repco engineer Nigel Tait, and Brabham BT19 Repco. Sandown Park Melbourne for its Tasman Series debut, January 1966. RB620 ‘E2’ engine in 2.5 litre capacity. (Australian Post magazine)

rb 620

Repco Brabham ‘RB 620 Series’ 3 litre SOHC V8 engine. The ’66 World Championship winning engine. Circa 310BHP @ 8000RPM. Weight 160Kg. ‘600 series’ block was F85 Oldsmobile based, ’20 series’ heads early cross-flow type (Repco)

In the last Repco article we start with a summary of the events leading to Repcos’ involvement in Grand Prix Racing, identify key team members, the equipment used to build the engines and finally a detailed account of the 1966 championship winning engines construction…

records

RBE factory records ’60’s style (Wolfe)

Why did Repco Commit to Grand Prix Racing?…

Younger readers may not know the background to Australian automotive company, Repco’s involvement in Grand Prix racing in the mid-60’s.

Coventry Climax, the Cosworth of their day caused chaos for British GP teams when they announced they would not build an engine for the new 3 litre F1 commencing in 1966.

Repco had serviced the 2.5 litre Coventry Climax 4 cylinder engines, the engine ‘de jour’ in local Tasman races, but were looking for an alternative to protect their competitive position, Jack Brabham suggested a production based V8 to them.

Brabham identified an alloy, linerless V8 GM Oldsmobile engine, a project abandoned by  them due to production costs. Jack pitched the notion of racing engines of 2.5 litre and 3 litre displacements using simple chain driven SOHC heads to Repco’s CEO Charles McGrath.

GM developed a family of engines, the F85 Oldsmobile and Buick 215, almost identical except that the F85 variant had 6 head studs per cylinder rather than the 5 of the 215 and was therefore Brabham’s preferred competition option.

Jack had seen the engines potential racing against Chuck Daigh’s Scarab Buick in a one off appearance by J Lance Reventlow’s outfit at Sandown, Australia, in early 1962. The engines competition credentials were further established at Indianapolis that year when Indy debutant Dan Gurney qualified Mickey Thomson’s 215 engined car 8th, the car failing with transmission problems after 92 laps. It was the first appearance of a stock block engined car at Indy since 1945.

scarab

Jack Brabham looking carefully at the Buick 3.9 litre engine in the mid-engined Scarab RE at Sandown Park, Melbourne in 1962, filing the information away for future reference! (Doug Nye with Jack Brabham)

Whilst the engine choice was not a ‘sure thing’ its competition potential was clear to Brabham, as astute as he was practical. At the time the engine was the lightest mass production V8 in the world with a dry weight of 144kg and compact external dimensions to boot. Its production future at GM ended in 1963 due to high production costs and wastage rates on imperfectly cast blocks, about 400,000 engines had been built by that time.

New Kid on the Block…

‘Having talked my way into the Repco Brabham Engine Co with a promise of hard work and a 3 weeks trial I was very happy’ recalls Rodway Wolfe.

‘I was given a nice grey dustcoat with a lovely Repco Brabham insignia on the pocket and shown around the factory and introduced to everyone. I was the seventh employee. Repco had picked the cream of their machinists from throughout the Repco empire, they were great guys to work with and willing to share all their skills.

The three-week trial period was a gimmick, after a few days I had settled in as one of the team. After the trial my wage was increased to slightly higher than my previous job in the Repco merchandising company.’

People: Key Team Members…

dyno

L>R: Phil Irving, Bob Brown, Frank Hallam and Peter Holinger dyno testing the first 2.5 litre Tasman RB620 engine at Russell Manufacturing’s engine test lab in Richmond in March 1965. Weber carbs borrowed from Bib Stillwell, the engine did not race in this form. The engine initially produced 235BHP @ 8200RPM, equivalent to a 2.5 Coventry Climax engine. ‘Ciggies a wonderful period touch (Repco)

‘The first prototype RB engine was built at the Repco Engine Laboratory in Richmond, Victoria (an inner Melbourne suburb, then a hub of manufacturing now a desirable inner city place to live, 1.5 km from the CBD) and was designated the type ‘RB620’, which was the file number of the various laboratory, research and development projects in process.

Frank Hallam was GM and Phil Irving Project Engineer together with Nigel Tait. Michael Gasking and Peter Holinger made the components and tested the engines. There were others involved before my time, those above were involved at Richmond’.

As an industrial site using steel garages in Richmond the RB project received comment in various overseas publications in 1966 of the ‘World Championship Fl engine built in a tin shed in Australia’.

‘When I joined in late 1965 the project had just arrived at the Maidstone, Melbourne factory. (87 Mitchell Street, Maidstone, then as now an industrial Melbourne western suburb, 10 km from the CBD) The Manager was Frank Hallam. In the drawing office, the Chief Engineer was Phil Irving, Production Manager Peter Holinger, Production Superintendent Kevin Davies, the machine shop leading hand was David Nash. We also had a Commercial Manager, Stan Johnson who came and went’.

hallam

Frank Hallam and Jack Brabham discuss the turning of camshaft blanks on the Tovaglieri lathe (Repco)

‘Around this time Michael Gasking also transferred from the Richmond laboratory was Chief of Engine Assembly and Testing.  Also on the machine tools was John Mepstead who was a great all rounder and later appointed to help Michael with engine assembly. He eventually joined Frank Matich to ‘spanner’ the 1969 Australian Sports Car Championship winning Matich SR4 Repco.

Frank Hallam arranged for me to attend RMIT night school, Repco picked up the bill. Those Tuesday and Thursday nights for 4 years helped me immensely, over the period I obtained a certificate in ‘Capstan and Turret and Automatic Screw Machines’ operation and a certificate in ‘Product Drafting’. My status was as a First Class Machinist in the Repco Brabham factory.

If I had any queries I would also ask Phil Irving who loved a yarn and he used to be a huge bank of knowledge. I felt so honored to to work for him, and learned so much from him’.

RBE formation

‘Repco Record’, the internal Repco staff magazine announces the formation of Repco Brabham Engines Pty. Ltd. (Repco)

Machine Tools…

‘Frank Hallam was a machine tool enthusiast. It was a big help, he made sure we worshipped our machines, blowing away the swarf with an air hose. I learned respect and cleanliness of all machine tools. Few machine shops are as clean or free of swarf and mess everywhere with the exception of Holinger Engineering, Peter was also fastidious.

We were lucky to have top machines in the workshop. Our biggest was an Ikegai horizontal boring machine. RBE had 2 lathes; a Dean Smith & Grace English machine and also a Tovaglieri Italian unit. We had a small Deckel horizontal borer and a couple of mills, a Bridgeport and a French Vernier. The older machine was a Herbert capstan lathe, I used this making every stud for all the future Repco Brabham engines. Main bearing and cylinder head studs, a very big variety in different steel types, repetitive stuff that would normally be boring but I didn’t care, we were winning the World Championship’…

‘When he drew a new design of stud, Phil Irving would come out and check out my thoughts on being able to make it with what we had and other various things. We would do a yield point test in a vice where we measured the length of the new stud after I made a sample and then tension it to a nominated foot pound tension and we would keep increasing the tension until the stud refused to return to the original length. That tension was known as the yield point so Phil would pick a tension somewhere in a safe range under that yield point’.

RB620 Series Engine: Machining & Modification of the Olds F85 block…

olds

Not the sharpest of shots but a rare one showing the ‘production’ Olds and RB620 engines. RB620 on the right. The engine was the lightest production V8 in the world at the time (unattributed)

‘When I arrived there were a lot of aluminum cylinder blocks along one factory wall. Repco acquired 26 Oldsmobile cylinder blocks from General Motors in the US. (2 of the 26 were prototype engines E1 and E2 which were built up in Richmond)

One of my first jobs was to remove all the piston assemblies from those 24 blocks. They were not short blocks as known in Australia (here they are complete without sump or cylinder heads) but these were not complete to that stage. They had crank bearings in place, all main bearing caps and the 3.5 inch liners were cast in the block. We didn’t use the cast iron main bearing caps or bolts, replacing them with steel caps and high strength studs.

The RB 620 used the original 3.5 inch cast in sleeves but practically everything else was changed. All surfaces were re-machined for accuracy, all bolt thread holes re-tapped and recessed to accept studs of superior material. The camshaft bearings were in the valley of the block of course but we pressed them out and rotated them 45 degrees and pressed them back in place to cut off the original oil galleries as our engine ran twin overhead camshafts, one per cylinder bank’.

‘The front original camshaft bearing was left intact and the second camshaft bearing was removed and fitted was a sleeve with an INA roller bearing. We made up little jackshafts which were driven from the crankshaft by a duplex chain, which also drove the single row chain driving the overhead camshafts. These jackshafts used the first original Oldsmobile slipper bearing and a small roller type bearing in the second original cam bearing location. The chains etc.were all enclosed inside the RB chain case.

rb 620 chain case

RB600 F85 Olds block from above. Note the valley cover of aluminium sealed ‘with a sea of araldite then painted over with Silverfros, those blocks which are still in service today still retain the araldited plate and still do not leak’ comments ex RBE engineer Nigel Tait. Phil Irving’s design had lots of clever bits including the timing chain arrangement which allowed the heads, also clever as the same head could be used on either side of the engine, to be removed ‘in the field’ without disturbing the engines timing (Tait/Repco)

block & timing case

600 block and timing case, ‘Purolator oil filter housing, timing chain single row (Repco)

‘A lot of people in 1966, including the international motoring writers did not realize the extent of the machining of the F85 Oldsmobile cylinder block to use as our engine base. It was more work and more involved in adapting the F85 than machining our new Repco cast blocks (700 and 800 Series) used later in the project.

It used to annoy all of us when our Repco Brabham engine was referred to as ‘Based on a Buick’ in various world motoring magazines. It also added insult to injury by adding ‘Built in a Tin Shed in Australia’!

‘We then had to close up the large cavity in the valley where there used to be a cover plate, pushrods and cam followers in the original engine. We spent many hours fettling aluminum plates by hand and fitting them into the valleys to cover the original cam followers and holes etc. When we had a very good fit of these plates we mixed 2 pot resin (Araldite) with additional aluminum powder and filled up the valley seams around the plate. Then with some elaborate heating systems we invented, we dried the araldite in place. This also gained us the reputation of the ‘The Grand Prix engine held together with Araldite’ in various motoring magazine articles!’

rb 20 block

RB600 block on the left, Olds’ F85 unmodified block on the right. The 600 block has the pushrod holes covered with the araldited aluminium plate. ‘The 1/4 inch thick block stiffener plate protrudes from the top of the modified block. This gives the effect of cross bolting…note also the Repco designed magnesium sump’ notes Tait (Tait/Repco)

‘I finished the job of dismantling the blocks, we only worked on 2 or 3 at a time during the early months of 1966. Unless the parts were an easy item or required substantial machine set up we only made a few of each component as design changes were ongoing. Not critical large changes but small subtle ones’.

‘We didn’t have any problems with the Oldsmobile block. There was one race in 1966 when a cylinder liner failed. As explained, we used the cast in liners and retained the 3.5 inch bore. BRO, (Brabham Racing Organisation) sent back the failed engine block and we bored out the remains of the cylinder liner. There was a casting cavity behind the liner which caused the weakness and failure. This was a problem that could not be dealt with without boring out all the liners and fitting sleeves. Otherwise there could be more failures due to bad castings. From that date we used dry liners and eradicated the risk of it occurring again.’

block

Jack and Phil specified this aluminium plate to add stiffness to the production F85 Olds block, big holes to provide rod clearance obviously. ‘This block would have had dry sleeves which lead to considerable blowby problems due to distortion and eventually wet sleeves were specified by Phil Irving’ notes Nigel Tait (Tait/Repco)

UK Components: Crankshaft Etc…

Phil Irving completed most of the design of the engine in England, he rented a flat in Clapham in January 1964 close to BRO and together with Brabham they settled on a relatively simple SOHC configuration, compatible with the block and fitment into the unused BT19 spaceframe chassis when the engine for which it was designed, the Flat-16 Coventry Climax was not used.

To expedite things in the UK, whilst simultaneously mailing drawings to Australia, Phil  commissioned Sterling Metals to cast the heads. Prior to his return to Australia in September 1964, HRG machined an initial batch of 6 heads, fitting valves and seats to Irving’s specifications.

‘Laystall in the UK also made the crankshaft. Constructed from a single steel billet the ‘flat’ nitrided crankshaft was a wonderful Irving design. I don’t recall any updates or changes to the design to the crankshaft over the years the RB engines were built. It was supplied in 2.5, 3 and 4.2 litres for the Indy engines. Also 4.4 litres and 5 litre sportscar versions. All crankshafts were of the same bearing dimensions etc’.

‘The term of ‘flat-crank’ refers to the connecting rod journals being opposite each other and not in multi-plane configuration as is usual in production V8’s. It meant  not such a well balanced engine at low revolutions but it actually converted the engine to virtually two four cylinder units and either cylinder bank would run quite smoothly on its own. The layout also enabled superior use of exhaust configuration eliminating the need for crossover exhaust pipes to obtain full extraction effect’.

crank

Crankshaft was made by Laystall to Phil Irvings design, pistons and rings by Repco subsidiaries. (Repco)

Pistons…

‘Repco is a piston ring manufacturer and very experienced in ‘ring design which meant that we were ahead in terms of the ring design. The famous SS55 oil rings were well known already around the world. The pistons were Repcos’. No other F1 engine constructor of the sixties made their own pistons. The experience gained with the supply of Coventry Climax pistons and rings contributed to this success.’

Bearings: Vandervell Interlopers! And ‘Racing Improves the Breed’…

‘Repco was already supplying engine bearings to various manufacturers globally from the Tasmanian based Repco Bearing Company, we obtained these components as required.

During 1966 an advert appeared in a British motoring magazine, ‘French Grand Prix won on Vandervell bearings’. Vandervell are of course a British bearing company, Repco were furious and telex messages to and from BRO (Brabham Racing Organization) revealed that Jack Brabham was not happy with the depth of the lead overlay on our copper/lead crankshaft bearings.

Our bearings had a lead overlay of .001inch and the Vandervell bearings an overlay of .0005. So I was instructed to pack away all our existing bearings and mark them not for use, our bearing company came up with the improved design bearings with the lesser overlay in time for the next GP. Racing certainly improves the product!

Before I transferred to the RB project and worked in Repco merchandising I received brochures and information about a new Repco alumina/tin bearing known as the ‘Alutin’ and advertised by Repco as a new high performance product. Repco were promoting them as a breakthrough design. I learned these new bearings had been unsatisfactory under test in the F1 engine and within a short period no more was said about the new product ‘Alutin’ . They were inclined to ‘pick up’ on the journals at high rpm. Another example of how racing  improves the product. This had not been evident in automotive engine testing by Repco to that date.’

ad

‘Racing Improves the Breed’…Repco Ad 1966

Outsourced Items…

‘There were some components we did source outside the Repco. There were cam followers, Alfa Romeo cam buckets, valve springs from W&S, valves manufactured by local company Dreadnaught. The ignition system was sourced from Bosch by Brabham.

The collets were from the UK and were a production car or motorcycle collet, the name escapes me. We made the valve spring retainers and collet retaining caps. Over the project we made  changes to the collet retainer material from aluminum  to heat treated aluminium bar and later titanium. Not a lot was gained as titanium fatigues as well, as we found out.’

Lucas Fuel Injection…

‘The fuel injectors and fuel distributor were Lucas items, although the system was in early stages of development. The system consists of an injector for each cylinder, in our case installed in the inlet trumpet a short distance from the inlet port in the cylinder head.

The system is timed with a fuel distributor in the engine valley driven from the chaincase by the distributor drive gear. The fuel is supplied at 100psi from an electric pump. The fuel pressure supplies and operates small shuttles which are constantly metering supply according to the length of shuttle travel. The amount of fuel supplied to the injectors is controlled by a variable small steel cam which is profiled to suit the particular engine size etc. The steel cam therefore controls the actual fuel mixture and is linked to the throttle inlet slides’.

‘It is interesting to note that although the fuel distributor can be timed to any position in the engine cycle, injecting at the point of the inlet valve opening or with it closed or wherever, it does not make any important difference in engine performance but as Phil Irving explained to me there is a point of injection that lowers engine performance so therefore the fuel distributor is timed in each installation to avoid the undesirable point of injection. The air inlet trumpets were cut to length spun and profiled’.

‘The chaincase was a magnesium casting and the ‘620’ 1966 World Championship engine used a single row handmade chain imported from Morse in the US. We cut all the sprockets and manufactured all the camshaft couplings etc. We used an SCD hydraulic chain adjuster, a standard BMC component.

The cam chain was driven by a small jackshaft which was fitted in the front two original camshaft bearing spaces of the original Olds block. The jackshaft was driven by a Morse duplex chain from the crankshaft sprocket, also Repco made. The crankshaft had a small gear driving the oil pump mounted underneath the chain case.’

chain case

Assembly of chain in the magnesium timing case of an RB620 engine (Repco)

Oil Pump…

‘The oil pump was a wonderful Irving design, simple to service but a small work of art. It featured flexible supply hoses with snap fittings and was a combination of oil supply pump which supplied the engine with oil up through a gallery in the chaincase and also a slightly larger scavenge pump connected to each end of the engine sump, also a magnesium casting. The pump assemblies, sump and all components were made by Repco.

The system consisted of a sump with an inertia valve located in its lowest point. If the car was braking the inertia moved the valve forward which opened a cavity in the front of the sump causing oil to be drawn from the front. Under acceleration the inertia valve moved backwards and the forward cavity closed and the rear cavity opened. This meant a minimum of blowby and air to be pumped by the scavenge system. I don’t recall any failure of this system apart from the  Sandown debut race of our ‘620’, 2.5 litre engine in January 1966′.

‘The ‘Tasman’ cars were held on the grid for rather a long time, the oil had cooled in the Repco Brabham. Jack left the line with plenty of revs, the cold oil and resulting oil pressure split the pressure pump gears. The first engines used cast Fordson Major tractor pressure pump gears and one gear had split due to the extreme pressure. Jack Brabham did  3 or 4 laps from memory.

I arrived at work on Monday morning and in typical Irving style found a drawing  for the supervisor for the construction of new steel gears and a ‘Do Not Use’ request for all stock Fordson gears. Phil had arrived at the drawing office on Sunday evening after the Sandown meeting and made the modifications straight away’.

‘The chaincase featured a couple of inspection caps which were removed to allow for chain tension adjustment etc. We made these caps and when it came to cutting the retaining threads in the chaincase we could not obtain the required thread tap anywhere. Phil had specified similar threads to the Vincent Motorcycle chain adjuster cap threads so that’s exactly what we used. Phi Irving brought in the original Vincent Motorcycle thread tap and we used that to thread all the chaincases under manufacture at the time, actually going back to valve spring collet retainer caps.

I recall that the first engines used BSA Motorcycle collet retainers. One of the things I enjoyed so much working with Phil was that he did not waste time on risk taking design, he used tried and tested systems from his past. He once said ‘There is really nothing new, it is just changed around in some way’… well he sure proved that with the first RB620 engine!’

chaincase componentry

Cylinder Heads…

‘The cylinder heads were cast aluminum of cross flow design, the cam covers cast magnesium. All our cast magnesium and aluminum components were supplied by CAC in Fishermans Bend, with the exception of the first batch of 6 heads cast in the UK. (Commonwealth Aircraft Corporation).

Phil was remarkable with his engine design skill in that he could see the item in reverse or 3 dimension and could design all the sand boxes etc and patterns required to arrive at the finished item.

The engine used no bolts as the original Olds did. Cylinder heads, cam covers, main bearing caps, sump, oil pump and chaincase were fitted with or retained by high tensile studs.That was my department and apart from the first couple of prototypes I made all the studs for the 1966/67 RB engines. Some were quite a challenge and the thread specification and tolerances were exacting.

The crankshaft rear bearing seal was a slipper ring design with a bolted on ring retaining flange. The slipper rings were supplied by our Russell Manufacturing Co, we made the outer flange in the factory. The steel flywheel was turned and made by Repco’.

Conncting Rods and Ease of Servicing…

rod

RBE conrod drawing (Repco)

‘We used modified Daimler connecting rods, competition Chevrolet and Repco rods. In later engines we occasionally used Warren rods from the US.

In the valley of the engine a small drive housing held the vertical ignition distributor and also the fuel distributor. Sometimes in the larger engines we also fitted a mechanical fuel pump to this housing. The type 620 engine engine had throttle slides running on small grooves with 1/8 inch steel rollers to prevent lock ups which would be a disaster. The slide covers were  fastened directly to the cylinder head and in later engines were changed to fully assembled units and fastened directly to the cylinder heads for ease of changing if required. They were then complete units with studs bolting them to the inlet flanges’.

A big feature of servicing the RB620 engine was that either cylinder head could be removed without disturbing camshaft timing or the camshaft from the cylinder head, a great time saver. (See the photos in the block section above which clearly shows this)

The oil pump can be removed in one small unit and replaced with no other dismantling. Or the two cylinder heads can be removed without disturbing the timing of the camshafts or the chain case. All very important design features, ‘in the field’.

engine assembly

RB620 engine assembly early 1966, Maidstone (Repco)

First Test…

The first engine, a 2.5 litre Tasman Engine ‘E1’ was fired up on March 26 1965, almost 12 months to the day Phil Irving commenced its design.

It was initially run with Weber 32mm IDM carbs and after a checkover fitted with 40mm Webers. The engine produced 235BHP @ 8200RPM, equivalent to a good Coventry Climax 2.5 FPF at the time.

Repco committed to build 6 engines for the 1966 Tasman Series, later changed to three 2.5 litre Tasman engines and two 3 litre F1 engines, the first race for the new engine was the non-championship South African Grand Prix on January 1 1966, the next part in the Repco story is the 1966 race program for the new engine.

rb 20 dyno long shot

‘2.5 litre 620 V8 E1 on the Heenan and Froude GB4 dynamometer in Cell 4 at Richmond, probably circa 1964/5. The exhausts lead straight out through a hole in the wall. Also there was minimal noise insulation in the tin shed that served as a test cell. Vickers Ruwolt across the road blamed us for the large crack that developed in their brick wall on the other side of Doonside Street!’ recalls Nigel Tait (Tait/Repco)

Photo & Other Credits…

Autocar, ‘Jack Brabhams World Championship Year’, Repco Record, ‘Doug Nye with Jack Brabham’, Australian Post, ‘From Maybach to Repco’ Malcolm Preston, Rodway Wolfe Collection, Nigel Tait recollections and his Collection, Repco Ltd photo archive

Etcetera…

letterhead

Original RBE Pty.Ltd. Letterhead. Jack Brabham had no financial (equity) or directorship involvement in this company, it was entirely a Repco subsidiary.

wade

‘E1’ was the RB620 prototype Tasman 2.5 litre engine. Most of the entries in this exercise book are dated, this one is not, but its mid 1965, the book records the use of cams with the ‘Wade 185’ grind and the valve timing, no dyno sheets sadly! (Wolfe/Repco)

repco 1

Have a look at this Repco film produced in mid-1965…

It covers some interesting background on the relationship between Brabham and Repco, footage of Jack at home in the UK, the Brabham factory in New Haw, some on circuit footage at Goodwood and then some sensational coverage of the 1965 Tasman Series in both NZ and Oz. The latter segues nicely into footage of the first ‘RB620’ 2.5 Tasman V8 engine ‘E1’ on the dyno at the Repco Engine Laboratory, at Russell Manufacturing, Richmond in ’65…

Next Episode…

Racing ‘RB620’ in 1966…

Tailpiece: #1-RBE620 2.5 litre ‘E1’, the prototype Tasman 2.5 V8, fitted with Webers on the GB4 dyno, Repco Engine Lab at Russells, Richmond 1965. The box over the Webers is for airflow measurement notes Nigel Tait…

rb 620 on dyno

(Tait/Repco)

 

 


 

 

RB Cover

This is the first Repco brochure about the RB project which fired my imagination to become a part of the project and off to Melbourne i went (Repco)

Mechanical Childhood…

I was born in Melbournes’ Kew and moved to Traralgon, in Victorias La Trobe Valley a long time ago! I suppose I can blame my lifelong interest in all things mechanical on my grandfathers as they were both blacksmiths. I have never been keen on horses and so I am possibly lucky that I was born after the motor car.

From a young age I was fascinated by anything with wheels or gears that whizzed around . My dad bought a new Ford Consul when I was 9, I studied it closely and learnt all I could. It was one of the first production cars with independent front suspension , dad would pull up in the main street and people would come up and push the mudguards up and down to show their mates how it worked, he used to get so annoyed!

He was a civil engineer and had 400 guys working for him at the local paper mill. In the early 1950’s he bought a derelict farm 10 km out of town. He loved farming but wasn’t very practical and he stayed at the paper mill and gradually improved the property on weekends.

In 1954 when I was 11 he bought a new Fordson diesel tractor. There were not many diesel’s on local farms, it was our pride and joy. I still have and use it! I learnt a huge amount from it. I remember when dad was at work I removed the Simms injector pump and pulled the governor apart and various pieces, Dad was due home so I stuck it all back together and went to start it, it wouldn’t! I hurriedly checked everything and figured out that because the injector pump had a small block coupling it could be put back 180’ degrees out of timing so I quickly removed all the pipes and refitted the pump and just managed to start the engine as dad drove up the driveway.

The Consul developed a bad flat spot when you accelerated . I reckoned it was a challenge , I pulled the downdraught Zenith carbie  to pieces. It had this funny looking thing held on with three screws on the side of the carbie and the book called it an economiser. I pulled that apart and the small rubber diaphragm had a hole in it. I put it all back together and during the week got another diaphragm from the Ford dealer. I fitted it on the following weekend and the Consul ran perfectly.

Dad told the whole world what a great mechanic I was, repairing something that the paper mills top mechanic could not etc,  that was my first mechanical victory!

ford consul

Dads Ford Consul taught me a lot and the independent front suspension was a Traralgon novelty (Wolfe)

Over the next few years I  had a Bedford truck given to me which I loved and knew every nut and bolt on as well. Dad bought me another ‘problem’ , in the mill workshop they had a small machine called a Calfdozer. Its a baby bulldozer built in England by Aveling Barford. The mechanics couldn’t start the engine, a Dorman single cylinder petrol unit. Dad bought it for me for 40 pounds, $80 now, and we lugged it home we could only unload it at a gravel pit we had so every bit of spare time I had was at the gravel pit trying to start this weird machine. It has a Zenith carbie as well, I first tested for spark of course and it had a wonderful big orange spark, after much fiddling with the magneto, timing and points it finally had a nice small blue spark and the thing duly burst into life. I still also have the Calfdozer and give it a run on occasion.

Bedford

This Bedford truck , bought by my Dad was one of a range of vehicles which taught me basic mechanics (Wolfe)

Motor Apprentice & Repco Rep…

All of this ‘fettling’ of machinery made my career path clear , dad agreed to me leaving school which I disliked very much! , but on the strict condition that I completed a motor mechanics course with RMIT by correspondence, which I did over 4 years, completing the practical elements some years later. I was encouraged to read books, no TV in those days but it was starting in the cities. I read all the motor magazines I could including ‘Wheels’ and ‘Modern Motor’, writing letters asking advice about my various farm engines. Phil Irving and Charlie Dean were my heroes, I read all I could about their projects including the Repco Cross-Flow head for the Holden ‘Grey’ motor.

I became interested in motor sport and bought the first Mini Cooper to be sold in East Gippsland, entering many hill climbs and usually winning the up to 1000 cc class. The first Coopers were 997cc ,only later did the 1275cc ‘S’ arrive . A few of us formed a new club, the Latrobe Valley Motor Sports Club’, its now known as the Gippsland Car Club .

In 1963 I read a local paper advert for employees required by Repco , they were opening an automotive workshop and parts store in Traralgon, I had since married and needed a better income than that derived on the farm . They didn’t offer me the manager’s job much to my disappointment but instead a drivers job distributing parts, engines and parcels . A new EJ Holden ute was mine, I did a huge amount of miles ,in those days, travelling up and down the Latrobe Valley in Gippsland Victoria sometimes twice in the one day. It taught me how to drive as things were totally different to today . The highways were pretty much free for all and there was no speed limit but if you exceeded 60MPH you had to prove in the case of an accident or incident that you were driving within your ability and safely. To give you an idea, the local police station in Traralgon had one car, a Ford Anglia with a top speed of about 70 MPH.

I enjoyed the job immensely and learnt lots of stuff in the workshop. Crankshaft grinding and cylinder head surfacing, clutch rebuilding etc. and of course engine assembly. I was lucky to work with the grandson of the Chairman of Repco’s Board, Sir Charles McGrath.

Mr David McGrath (brother of Sir Charles) was the managing director of our parts company and his son David junior was spending time in our particular branch learning the internal operations, he became a good mate and through him I learned a great deal about the parent company.

Repco owned ‘Brenco’ in Moonee Ponds Victoria , a machine tooling company,’ Warren and Brown’ in Footscray, a hand tool company and ‘PBR Brakes’ in Moorabbin and so the list went on. Each entity had a director on the Repco Board ,i was to learn a lot more of the politics of Repco as time went on.

On the road to Repco Brabham Engines…

RB fullspread

One of my tasks was to organise brochures etc, to be packed in each parcel we consigned. One day I received a bundle of these telling of the proposed development of a Repco Brabham Formula One engine. I read every word and decided that was what I wanted to do!

The following week the Melbourne Motor Show was on, I took the long train ride Melbourne for the show. Pride of place on the Repco stand was the prototype RB engine. There was a young fellow in a suit looking after the display , I asked him a few questions. He couldn’t really answer me and told me he was a student draughtsman helping Phil Irving in the drawing Office. That was enough for me, if this guy worked there so could !

I got him to divulge where the engine was being built, out in Maidstone near Footscray to Melbourne’s inner West. The following day, Monday, I took a ‘sickie’, hired a taxi and ventured out to Maidstone. After a lot of driving and walking around I found a small group of factories. They were ACL factories (Automotive Components Limited). ACL was operating under licence to an American Company , they manufactured in Australia, ‘Perfect Circle Piston Rings’, ‘Glacier Bearings’ and ‘Polson Pistons’. In the prior year the American company made moves to take over ACL, as this would have been a disaster for Repco, it was decided by Repco to buy ACL. So I arrived at these 3 factories, one of the empty ones had been assigned for the RB project.

I banged on the door , a guy answered but no way was he going to let me in. He explained that it was a special project and not open to the public. I gave him my whole story, he seemed to be happy that I was already a Repco employee. Finally Kevin ,let me in , I could see about 8 machines and 6 guys working making various components. I explained to Kevin that I would love a job there.

He was a bit taken back ,he told me these are Repco’s top guys and very special operators. I was young and confident and told him I would sweep the floor or anything if he would consider me. We stood and watched a guy turning something in a lathe, as I stood there an older guy wandered across to talk to the lathe operator. It suddenly struck me that this was the legendary Phil Irving standing beside me. In person, I could not believe it!

I took up the subject of a job again and he asked if I would like to look over a piston ring factory ? Anything to please Kevin as by this time I learned he was the works superintendent. He took me into the adjacent factory and introduced me to the manager, saying he would see me later and off I went , the Manager was good ,he stopped the machines, mainly operated by women , to show me what they were doing and held up various production lines to show the finished products . I now know that Kevin had arranged the factory inspection to have a second opinion on me.

I went back to Kevin and he said’ look we have decided to give you 3 weeks trial, but you will have to accept a lesser wage than you are presently getting in the country’. That didn’t worry me to work for Phil Irving, I would have worked there for nothing ! So I had to go home and tell my poor young wife that we were moving to Melbourne. I did not have a clue where to, all I knew was I had my job at Repco Brabham Engine Co and I was happy!

And so, an incredibly challenging but successful part of my life commenced…

RB detail 2

performance 2

 

film

tailpiece