Posts Tagged ‘Brian Hart’

Jim Clark, Lotus 35 and the Cosworth SCA F2 Engine…

Posted: November 6, 2017 in Who,What,Where & When...?
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(Gordon)

Jim Clark’s Lotus 35 Ford Cosworth SCA 1 litre F2 car at rest in the Pau paddock on the 25 April weekend in 1965…

You forget what delicate little flowers these cars were. When I glanced at Ian Gordon’s wonderful shot I initially thought it was a ‘screamer’, a 1 litre F3 of the same era. Not so.

Remember the pantheon of single-seater formulae at the time was 1.5 litre F1 engines giving 205-215’ish bhp, 1 litre pushrod F3’s breathing through a single carburettor choke giving about 100bhp and 1 litre OHC race engine F2’s giving 115 initially towards 150 bhp plus by the formula change to 1.6 litres in 1967.

Jim won at Pau from Dick Attwood’s Lola T60 SCA and Jochen Rindt, also SCA powered in a Brabham BT16.

The engine in Clark’s winning Lotus is Keith Duckworth’s conception based on the production Ford 116E block. The SCA (single cam series A) was the dominant F2 engine of 1965. It won all of the ‘Internationals’- there was no European F2 Championship until 1967, with the exception of the ‘Autocar Trophy’ at Snetterton in May. Graham Hill took that win, BRM P80 powered, aboard a John Coombs Brabham BT16.

Hewland ratio change in Jacks BT16 in the Pau paddock- there were lots of them as Brabham tried to match ratios to the peaky 1965 variant of Honda’s S800 engine. Brabham raced much of the ’65 F2 season in SCA powered cars as Honda development continued (Gordon)

Ian Gordon became a well known and respected Australian race mechanic, later working for Alec Mildren Racing and Max Stewart amongst others. He was on a racing holiday in 1965 and snapped these fantastic photos of the ‘F2 Engines of 1965’ during the Pau Grand Prix weekend. The engines are the SCA, BRM P80 and Honda S800.

For Jim it was the first of five F2 wins in ’65- that amazing season of Clark domination (F1 World Title, Tasman Championship and Indy 500 win), the others were at Crystal Palace, Rouen, Brands Hatch and the Albi GP late in the season.

The real threat to Cosworth SCA dominance into 1966, not that it was necessarily apparent at the time, were the 1 litre DOHC, injected Honda 4 cylinder engines fitted to various of Jack’s works Brabhams during 1965. The peaky nature of the engines power delivery was the primary issue which was addressed in spades over the winter. Click here for my article on Brabham Honda dominance in 1966.

https://primotipo.com/?s=brabham+honda

Duckworth’s First Cylinder Head Design…

By the beginning of 1963 new F3 and F2 categories were announced, the former to replace Formula Junior to take effect from 1 January 1964.

Duckworth, armed with 17,500 pounds of support from Ford set to work on the new ‘SCA’ engine which would use the Ford 116E block known so well to them.

Sitting atop it would be an aluminium cylinder head with a line of vertical valves, two per cylinder ‘It was really an overhead cam version of the last Formula Junior engine’ Duckworth quipped in Graham Robson’s wonderful ‘Cosworth’ book.

The engine was notable for its bowl in piston combustion chamber or ‘Heron Head’ design. ‘My simple argument was that at the compression ratios we could use, and the valve sizes needed to ensure good breathing, that a bathtub type of chamber ended up masking the valves. It was an awfully long way around their periphery. I argued with myself, that if I put the combustion chamber in the piston, then for most of the time the valves would be out of the way, and that they wouldn’t impede the flow’ Duckworth said.

The steeply aligned inlet port of the SCA owed much to the Mk XVII pushrod 1963 engine engine which was heavily modified by having tubular downdraught inlet ports brazed into the casting. It wasn’t easy to do or cheap to make but improved gasflow. The SCA in some ways mirrored that approach.

KD ‘The SCA was the first cylinder head that I ever designed, and now I think their was quite a lot wrong with it. We had all sorts of trouble with the combustion- we couldn’t make it burn- but it was still good enough to win a lot of F2 races. In the end there was so much spark advance, that it wasn’t reasonable. We ended up with 49 degrees. The SCA chamber suffered from a lack of circumferential swirl’.

Colin Chapman sub-contracted the running of his F2 team to Ron Harris, the two wheels of the car alongside Clark’s Lotus 35 in the opening photo are those of his teammate Brian Hart- Brians 35 is BRM P80 powered and is shown above. The story of BRM’s 4 cylinder P80 F2 engine is one for another time but its vital statistics are an all aluminium, DOHC, 2 valve, Lucas injected 998cc (71.88X61.6mm bore/stroke) dry sumped motor giving circa 125 bhp @ 9750 rpm. (Gordon)

 

BRM P80 1 litre F2 engine cutaway (J Marsden)

Duckworth- ‘It might not have been right, but we had to make it work. It won the F2 Championships of 1964 and 1965…and…until the Honda engine of 1966 with four valves and twin overhead camshafts, tungsten carbide rockers and torsion bar valve springs appeared in Jack Brabham’s cars. We’d run out of breathing at 11,000 rpm so we obviously needed more valve area. That’s what started me thinking about 4-valve heads’.

‘Mike Costin  and I exercised great ingenuity- we had ports that curved around, we had the piston of the week with every kind of shape, dint and odd hole- but the combustion was not good, the mixture never burned properly’.

All the same, the dominant F2 engine of 1964 and 1965 did so producing between 115 bhp @ 8700 rpm in its original Weber 40 IDF carburettor form and ultimate ’66 spec Lucas injected form 143 bhp.

Ford 5 bearing 116E block. Single, (train of seven gears) gear driven overhead camshaft, two valves per cylinder , Cosworth rods and pistons, Laystall steel crank. 997cc- 81mm x 48.35mm bore-stroke.

SCB variant 1498cc 175 bhp – 3 engines only built including the Brabham BT21B raced by ex-Brabham mechanic Bob Ilich in Western Australia

SCC variant 1098cc 135 bhp for North American sportscar racing

Bibliography…

‘Cosworth: The Search for Power’ Graham Robson, tentenths.com, F2 Index

Photo Credits…

Ian Gordon, Peter Windsor, John Marsden

Tailpiece: Jim Clark’s Lotus 35 Cosworth SCA on the way to victory in the 80 lap, 221Km Pau GP on 25 April 1965. Its only when you look hard you realise that it is not an F1 Lotus 33!…

(Windsor)

 Finito…

Hart Attack…

Posted: October 21, 2016 in F1, Fotos
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Jones in the Lola THL1 Hart, Monaco 1986, Q18 and DNF after a collision on lap 2. Patrick Tambay’s performance was perhaps more indicative of the cars speed, Q8 but again DNF after an accident. Prost won in a McLaren MP4/2C TAG Porsche (Getty)

Alan Jones in his Lola THL1 Hart at Monaco during practice on May 10 1986…

Just looking these pictures, note the Ford logo on the side of the cockpit, reminded me of the vexed, too soon launched Ford Cosworth GBA 1.5 V6 twin-turbo.

Jones and Tambay didn’t race the Ford engine in ’86, they contested the title with Brian Hart’s Hart 415T, 4 cylinder engine whilst GBA development continued at Cosworths. Best results for the year were a 4th and 5th in Austria in a sea of DNF’s. The Haas team then withdrew from F1, the GBA program torch carried forward by Benetton but not for too long…

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The tiny Ford Cosworth GBA; 1497cc, 120 degree DOHC, 4 valve V6 twin-KKK-turbo, circa 750bhp, depending on month and spec, engine during the British GP weekend, Brands Hatch 1986 (Schlegelmilch)

That Brian Hart built an F1 engine is an accident of history. It was an evolution of the relationship he had with the Toleman Team who won the European F2 Championship in 1980 (Brian Henton won the drivers title) with his superb 2 litre 420R 4 cylinder engine (below) in the back of Rory Byrne’s TG280 ground effects chassis.

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The 420R engine cutaway, note belt driven camshafts, engine extremely compact and beautifully packaged, an evolution of his FVA and BDA knowledge including his design/development of the alloy 2 litre BDG block (John Way)

 

The 420R engine has a bore/stroke of 93.5 mm x 72.6 mm, a capacity of 1994 cc and was the result of a long development path starting with Hart’s race preparation of FVA’s in 1969. Designed in house, blocks and heads came from Stirling Metals with the machining done at Harts. Gordon Allen produced the cranks, Hart did his own cams and developed the pistons with Mahle in Germany. Lucas provided the fuel injection. The engine developed 305 bhp @ 9,500 rpm with safe bursts to just over 10,000 rpm.

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Toleman TG280 Hart cutaway, 1980 Euro F2 championship winner in Brian Henton’s hands with Derek Warwick fidhting him all the way in the sister car. Aluminium ground effects monocoque chassis, Hart 420R engine, Hewland FT200 5 speed transaxle. In 1981 Lola built customer versions of this design (Alenso)

Ted Toleman’s wealth derived  from building up the UK’s largest car transport business, his ambition extended to graduation from F2 to F1. Rory Byrne designed what became the TG181 chassis which team manager Alex Hawkridge told Brian would either carry a turbo-charged version of the 420R or Lancia’s turbo 1.4 which was doing service in their sports-racer at the time. So Brian set to with the challenge!

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Brian Hart shows journalist Maurice Hamilton his handiwork in March 1982. Early test of the turbo-charged 415T engine. Look at that early turbo/inlet manifold (Hamilton)

‘I had never even seen a turbocharger,’ Hart claims, ‘and I didn’t understand intercooling’. His engine was the first British turbo Fl engine and the TG181 was as ‘big and butch’ as the TG280 was ‘nimble and slinky’. Packaging of these early turbo-cars was a big challenge even with the resources of Ferrari whose 1981 126CK was no picture of elegance either.

The first beautifully integrated turbo was John Barnard’s 1984 McLaren MP4/2 TAG Porsche largely because he prescribed very thoroughly the packaging of his engine spec to Porsche to ensure the needs of his chassis, particularly its aerodynamic effectiveness were not compromised by the engine and its ancillaries inclusive of radiators and intercoolers.

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Monobloc all alloy Hart 415T, note belt driven cam drive and atypical Holset turbo, spec of engine as per text (John Way)

The first iteration of the 415T had a bore and stroke of 89.2mm X 60mm and a capacity of 1499cc. With a compression ratio of 6.7:1 and single KKK turbo-charger the engine developed circa 557bhp at 9500rpm compared to its competitors; normally aspirated Cosworth DFV circa 500bhp and Matra V12 510. The turbos were the Renault V6 540, Ferrari V6 560 and BMW in-line 4 557bhp.

The 415T engine was down on power and prone to head-gasket failure, drivers Brian Henton and Derek Warwick who had enjoyed so much Hart F2 success in 1980 repeatedly failed to qualify.

Hart was under lots of pressure and there was heavy tension between him and Byrne noting the shortcomings of the latters chassis. Derek Warwick later observed that Brian was a great engineer, a great person and always under-financed. And a pretty handy driver in his day…

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Works Lotus F2 driver in 1964, here at Montlhery, Lotus 32 Ford Cosworth SCA. Brian was 4th behind Brabham, Stewart in the other Ron Harris entry and Jo Schlesser. Grand Prix de L’ile de France, 27 September 1964. Equal 13th in the Euro F2 Championship that year (Viollet)

Brian Hart raced with success, he dominated the 1172cc Clubmans formula and later raced in FJ, its successor F3 and in F2 during its most competitive period with grids full of ‘graded’, moonlighting GP drivers.

He raced the brilliant Mike Costin designed Protos 16 powered by a Hart prepped Cosworth FVA, a highlight setting fastest lap and finishing second to Frank Gardner’s works Brabham BT23 FVA in the slip-streaming blast title qualifier at Hockenheim in 1967. He was 11th in the Euro F2 Championship that year and 14th in 1968 driving a Merlyn Mk12 and Brabham BT23C both FVA powered .

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Kurt Ahrens ahead of teammate Brian Hart in sensational timber monocoque Protos 16 Ford FVA F2 cars during the ’67 German GP won by Denny Hulme’s Brabham BT24 Repco. Brian finished the race but was unclassified, F2 class won by Jack Oliver’s Lotus 48 FVA (unattributed)

He gradually phased from driving into building and developing race engines forming Brian Hart Engines in Harlow, Essex in 1969 gaining much success preparing and tuning FVA’s for racing and BDA’s for rallying. Ronnie Peterson won the Euro F2 championship in 1971 with a Hart prepared FVA (March 711M) and Mike Hailwood in 1972 with an 1850cc BDA. (Surtees TS10)

Brian originally trained at De Havilland Aircraft, then worked for Cosworths when they were building/developing the 1600cc Ford FVA F2 engine, the precursor to the great DFV in the initial 1966/7 partnership between Cosworth and Ford.

A turning point with the 415T was when Hart decided to build the engine as a monobloc, that is no separate head joint to be sealed against coolant, boost pressure and combustion leaks; ‘I decided to cast the head and block as one and in about a fortnight we gained 130bhp. Hart also used British Holset turbo-chargers and benefitted from their flexibility and willingness to develop their products to suit the engine. ‘And the new car (1982 TG183) was 90 per cent better’ Hart quipped.

The much improved TG183B scored 10 championship points in ’83. In ’84 F1 novice Ayrton Senna almost won at Monaco in the quicker TG184. Hart recalled working with the young champion ‘He was astonishing. No man until Schumacher could motivate a team like Ayrton. I asked him to remember the boost reading on one corner per lap, and he came back after a single lap with all the readings for every corner in his head. It was a new level of participation.’

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Ayrton Senna in the dry during Monaco 1984 practice, this overhead shot shows the innovative aero approach of Rory Byrne. Car a bit fugly but fast albeit not reliable enough, Toleman TG183B. The famous race was wet, it started 45 minutes late, the two Renaults collided thru no fault of their own on lap 1 giving Patrick Tambay a broken leg, setting the tone of the race. The chequered flag was waved early by (factory Porsche 956 driver) Clerk of Course Jacky Ickx, without consulting the Race Stewards, on lap 31 giving the Porsche powered Prost a win in his McLaren MP4/2 TAG from Senna who was chasing him down. Behind him Stefan Bellof was catching Ayrton hand over fist in his Tyrrell, having started the only normally aspirated car in the race from the back of the grid.To this day enthusiasts debate the race outcome had it gone a few more laps let alone the full distance, 76 laps. A collision between Senna and Prost giving Stefan the win or a collision between Senna and Bellof giving Prost the win my two potential outcomes! Bellof’s podium was taken off him later in the season as the Tyrrell was found to be underweight by the FIA. Read a report of this event, the twists and turns from Martin Brundle’s practice crash to Tyrrell’s exclusion months later amazing. The race was notable for the fine delicacy of control these two tigers (Senna and Bellof) exhibited in such difficult conditions on the most unforgiving circuit so early in their careers, greatness apparent to say the least, unfulfilled, sadly, in Bellof’s case of course (unattributed)

In 1985 development was hamstrung early in the year when the team could not test as they had no tyre contract, this problem was solved when they bought the Spirit teams contract when they withdrew from F1. By this stage with Holset turbo, Hart/ERA digital engine management and Marelli fuel injection at 2.5 atmospheres of boost the engine developed about 740bhp at 10,500rpm.

A fantastic moment was when the car qualified on pole in the German GP after second session times were impacted by rain. The engine was estimated to be giving about 825bhp in qualifying spec with about 730 in race spec but reliability to a large extent had been lost.

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Teo Fabi at Brands Hatch in the Toleman TG185 Hart during the ’85 British GP, DNF transmission from grid 9. Prost won in a McLaren MP4/2B TAG Porsche. Look at how neat the packaging of this car is compared with the earlier Tolemans, Rory Byrne and Brian Hart made great strides in development of both chassis and engines. The great shame is that none of Hart’s customers were ‘flush enough’ to fund a development program of Hart’s 415T to get the mix of power/reliability needed. Hart probably also shot himself in the foot by taking on more teams than he really had the resources to service properly. As you can see hindsight is a great strength of mine! (Fosh)

The Toleman team was acquired by Benetton later in 1985, who used BMW engines. It was a relief for Hart who struggled with small budgets and too many customers (Spirit, RAM and Beatrice-Lola) ‘I had my arm twisted to do other teams. Toleman simply couldn’t fund the development. I once told Paul Rosche (BMW’s engine guru) what we had to spend, and he said they spent that on blocks alone’ Hart recalled in a MotorSport interview.

Hart 415T; aluminium 4 cylinder monobloc weighing about 140Kg. Belt driven DOHC, 4 valve, fuel injected, intercooled and single Holset turbocharger 1459cc (bore/stroke 88X61.55mm). Between 650-825bhp at 10500 rpm depending upon spec and year.

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Bennetton B187 Ford GBA 1.5 V6 twin-turbo (unattributed)

Going back to the Ford GBA engine early in the article, Benetton raced the ‘works’ Ford GBA’s with a modicum more success in 1987, 5th in the constructors championship won by Williams Honda the best result that year a 3rd in Adelaide for Thierry Boutsen at the seasons end.

Into 1988 and rule changes tipped the balance a little more in favour of normally aspirated engines so Benetton raced the B188 powered by the 3.5 litre V8 Ford Cosworth DFR finishing 3rd in the manufacturers championship behind McLaren and Ferrari; Ford competitiveness was returning and the GBA was placed on the shelf a victim of rule changes and being a little too late to the turbo-party…

Credits…

MotorSport, Doug Nye ‘History of The Grand Prix Car’, Maurice Hamilton, Anthony Fosh, Rainer Schlegelmilch, Pascal Rondeau, John Way, 8W Forix, Alenso, Roger Viollet

Tailpiece: Brian Hart with his 830 V8 engine, it was fitted to the Footwork chassis’, 1996 Spanish Grand Prix…

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After working on the development of the Ford Cosworth  DFR in the early 1990’s Hart built the 72 degree 3.5 litre V10 ‘1035’ which was used by Jordan with successful results in 1993. For the 3 litre formula in 1995 he ‘chopped a couple of cylinders off’, maintaining the 72 degree Vee angle to create the ultra compact ‘830’ V8.

Known fondly as ‘Jam Tart’, this immensely popular member of the F1 paddock died too young at 77 in 2014.

Finito…