Posts Tagged ‘1964 Le Mans 24 Hours’


Jack Sears, Dunlop Curve, Le Mans in the ill-fated long, low, swoopy AC Cobra Coupe 20-22 June 1964…

Sears was hoping to do better than his marvellous fifth place at Le Mans in 1963 aboard the Maranello Concessionaires Ferrari 330LMB he shared with David Piper.

The talented British sedan and sportscar racer was partnered with Peter Bolton in the one of a kind AC Cobra Coupe, AC Cars Ltd owner Derek Hurlock and his team built to take on the ‘works’, Shelby Daytona Coupes in the famous 1964 24 Hour classic.

It was also a chance for AC to improve upon its 7th place finish at Le Mans in 1963 when the factory Cobra driven by Ninian Sanderson and Peter Bolton finished 7th.

The big Coupe was registered ‘BPH4B’ to allow some testing on public roads, despite this the first Carroll Shelby knew of AC Chief Engineer Alan Turner’s in-house design was at the car’s competition debut during the Le Mans test day in April.

Visibly lower than the Pete Brock designed Daytona coupe (41 inches compared with 48 inches- its height a function of uncertainty over Le Mans windscreen height regs) both designers sat the drivers lower in the car. Turner had also raked the windscreen, created a lower nose section and a longer flowing roof as well as designing the ‘eyebrows’ over the tops of the wheel arches he claimed help clean up airflow.

The cars promise of speed on the Mulsanne Straight was met- Bolton achieved the 27th fastest time in a fast run without ‘going for a time’ in a car which still required development.

Back in the UK brake overheating problems were addressed with ducting, a burned piston replaced and a rear spoiler added for stability and to reduce lift. The car was then tested at the MIRA facility for which it proved too fast, there was not a road section which allowed the car to run to its maximum speed…

AC’s Alan Turner created a marvellous, handsome, cohesive, masculine shape with demonstrable aerodynamic properties- such a shame only the one was built (Autocar)

During Le Mans Sears and Bolton were timed at 180.2mph @ 6300rpm, matching the Daytona Cobras despite giving away 30bhp to the Shelby entries- AC cars chassis #A98 had a 289cid/4.7 litre ‘Windsor’ engine which developed circa 355bhp, the Shelby cars had around 385bhp.

The car qualified conservatively second in class behind the Gurney/Bondurant Shelby entry and ran in that race position, at one point leading the class early in the race averaging 20mph for the first 3.5 hours.

The big coupe began to have fuel feed problems which were found after the race to be caused by newspaper in the fuel tank- sabotage- which blocked the fuel filter. Much time was lost as the filter blockage was diagnosed and remedied.

Circulating at the pre-race determined lap times the next stint was trouble free with the slippery machine able to match the Shelby’s top speed despite less power and a higher diff ratio (2.88:1 rather than 3.09:1- the fastest Daytona speed of the weekend was 186.4mph @7000rpm using the 3.09 ratio).

It was an unusually bitterly cold night for mid-summer with occasional patches of mist. Some reports have it that the teams tyre supplier advised not to change the cars tyres. At around 10.15pm on Saturday evening, with Bolton at the wheel a tyre blew at Maison Blanche- the car spun and was collected by Giancarlo Baghetti’s following works Ferrari 275P. The Ferrari speared off into the barriers and crushed three French, late teenaged spectators standing in a prohibited area.

The AC flew over the guardrails, lopping branches from trees at a height of 20 feet before coming to rest in a crumpled heap. Baghetti was uninjured with Bolton taken to hospital with minor injuries.

The best placed of the Shelby Daytona Coupes was the Dan Gurney/Bob Bondurant driven car which qualified 10th and finished 4th. Sears qualified his machine 13th, the Jean Guichet/Nino Vaccarella works sports-prototype Ferrari 275P 3.3 V12 won the race that year.

The wreck of Coupe A98 was brought back to the AC headquarters in Thames Ditton and never rebuilt and or raced further ‘in period’. The very significant car was restored by Barrie Baird who negotiated its purchase in 1972. The work took over 12 years, many of you will have seen it at Goodwood and the like.

What a superb looking machine the car is, Le Mans paddock 1964. #43 is the Hunt/Wagstaff Lotus Elite 22nd, #42 is the Lawrence/Spice Deep Sanderson 301 BMC DNF. What a magic atmospheric photo (ITMSP)

The high speed excitement about the AC Coupe started in much more amusing fashion, although it wasn’t seen that way at the time, not long before Le Mans.

Given the Motor Industry Research Association (MIRA) roads had not allowed a flat-out run AC decided to test the high speed stability of the car on Britain’s M1 motorway in an incident which has gone down in motoring lore.

‘Gentleman Jack’ Sears recalled the early morning run in articles published in ‘The Car Connoisseur’ and ‘Autocar’ magazines.

‘About a fortnight before Le Mans AC thought they really ought to try and test the car to see what top speed it was likely to attain. We decided to get up at dawn on this early June morning and do a run up and down the M1 motorway. There was nothing special about that in those days when the M1 was used by other manufacturers with nearby factories such as Jaguar, Aston Martin and Rootes Group (Humber, Hillman and Sunbeam-Talbot).’

‘So we all met at Southern Service Station, warmed the car up, and I went up the north carriageway for several miles, and clocked what I thought was terminal speed before returning south without passing any traffic – it being 4.30 am. Back at the service station I told them how many revs I’d done, they knew what the back axle ratio was, they knew what the tyres size was, the wheel size etc etc, and from their slide rules (no calculators in 1964) they discovered that we had done 185mph. Then Peter Bolton, who was to be my co-driver, went off and did the same thing. We were both happy with the car and by 8.30am I was back home in Norfolk eating eggs and bacon.’

‘Around lunchtime I took a call from a journalist on the Sunday Times who had somehow picked up the story in a Fleet Street wine bar from a chap called Tony Martin, Derek Hurlock’s nephew, who was on the administrative side of the paper and had been present earlier in the day. It must have been a ‘quiet news day’ because they blew up the story out of all proportion. It hit the headlines and the press followed the story right up to Le Mans, where sadly the car was destroyed after a rear tyre burst, putting Peter Bolton into hospital.’

‘I am actually the only man in the world who has raced a Shelby Daytona Cobra Coupé, the AC Car Company Cobra Coupé and the Willment Cobra Coupé.’

Sears AC during the early Saturday Le Mans laps, #18 the Aston DP214 driven by Salmon/Sutcliffe NRF , 250LM or 275P back a bit (unattributed)

Not too long after Le Mans Sears stopped racing to return to farming in Norfolk but he was still very much in demand as a test and development driver, but a monumental accident in a sports-racing Lotus 40 Ford at Silverstone came way too close to costing him his life, aged 35. It took him 12 months to recover but he never strayed far from racing, not least because his son David became a racer and team owner.

(B Bird)

In sequels to the M1 incident the publicity was very good for AC Cars, but the compulsory 70 mph speed limit introduced on British roads in 1967 was sheeted home to the exploits of AC and Jack!

He chuckled at the memory, ‘I took a lot of flak for being responsible. Indeed at the time there were those who felt that sort of speed on a public highway was irresponsible behaviour and I had to live with this for some time. I am glad to say that I was eventually exonerated when, towards the end of her life, Lady Castle was interviewed by Tony Martin and asked whether the story concerning his uncle’s car had any effect on her decision to impose the speed limit three years later. She remembered all the publicity but claimed that the speed limit was already under review long before – so I was vindicated!’

Wowee. Thames Ditton, AC Cars Ltd (Just a Car Guy)

Specifications in brief…

Three shots from ‘The Cobra-Ferrari Wars’.

Top-the Coupe body framework being constructed at Thames Ditton. Middle is the engine bay with the Weber 48IDA fed, cast iron, 355bhp pushrod 4.7 litre ‘Big Henry’ V8- what a marvellous race engine this ‘Windsor’ family of small block Fords is! At the bottom is Jack Sears alighting the car after THAT M1 morning run.

Etcetera: owner Barrie Bird adds…

A day after uploading this article ‘A98’s owner and restorer Barrie Bird kindly got in touch and added hugely to this story with some comments which are at the end of the piece in the readers comments area.

He also sent in some wonderful material, which he is sharing with us all- the first photos are ‘…ones of Jack on his farm and you can see the little farm roads which were traversed for half an hour or so at three figure speeds’.

‘Jack was very funny on the farm- he gathered a couple of his farm hands who knew what they were about and briefed everyone in very military and commanding style; “You will be positioned here, you will lookout for traffic there, the photographer will stand there. I shall only make two passes at low speed to be sure you get your shots”. So off he went at high speed, getting faster and faster, declining to stop, wearing a big grin all the while. Magic!’

(B Bird)

(B Bird)

(B Bird)

See the padlocked fuel caps below- ‘All I can tell you about the padlocked fuel caps is that the photo was taken before the race. Was it a case of bolting the stable door, or did the saboteur slip in during the refuelling? Who knows?’

(B Bird)

What a mess! A98 post Le Mans shunt- Peter Bolton was a lucky boy to escape with his life. The top front suspension leaf spring, steering rack, tank and a rocker cover are about all of the components I can pick.

(B Bird)

Barrie’s adds this piece about Jack Sears comments on the comparative merits of each of the different AC Coupes…

(B Bird)

Technical Specifications in Detail…

Barrie Bird advises as follows;

‘The specifications are in theory the same as the FIA homologation for the standard Cobra, except that, in those days, it was permitted to build a different body on the homologated chassis and still run as a production GT. I think this went all the way back to the inter-war years when the manufacturers would supply rolling chassis to be bodied by coachbuilders. In any event by 1964 this provision was being well abused and chassis modifications, ostensibly to support the special bodywork, were used to stiffen things up.’

‘A.C. to their great credit kept to the spirit as well as the letter of the law and A98 is quite usable on the road as a GT with a comfortable cockpit and a normal boot which will swallow a couple of big holdalls. The ground clearance has to be kept in mind and of course the car was designed before the era of speed bumps and potholes. The lowest point under the car is the diff. oil cooler and this does not take kindly to being in contention with tarmac!’

Dimensions et al

Wheel base 90 inches, Length 176 inches

Track Ostensibly standard at 51″ but in fact wider by reason of the largest homologated wheels 7.5″ front and 9.5″ Rear. The largest track is obviously on the rear and with the original Goodyears fitted increases to 66″

Weight at scrutineering 1964 le Mans 2482 Lbs. Weight in 1986, after reassembly, with tools, spare wheel & tyre, jack, oils and water, but without any fuel 2365 Lbs

Capacities- Fuel 30 Imp.Gals, Engine oil,wet Aviaid sump, 6 Imp Qts

Wheels and Tyres

Tyres Goodyear Bluestreak 26.5 x 8 – 15 and 26.5 x 10.5 – 15

Wheels Halibrand Indy 500 pattern WH6S 2528 and 2532 F & R 7.50″ and 9.50″. Often incorrectly described as ‘FIA Pattern’


Gearbox Borg Warner T-10 four speed. Nitride alloy gears ‘Pontiac Gearset’ – 1:1 – 1.31:1 – 1.637:1 – 2.196:1. Axle Ratio 2.88:1 Gearing in 4th gear 27.6 mph per 1000 RPM No allowance for tyre growth


289 V8, cid 4727 c.c. supplied by Ford Dearborn 355 bhp. Four 48 IDA Webers, ported big valve heads, high lift camshaft, standard High Performance crank and rods, HP 5 bolt block, damper and flywheel. Standard HP clutch

Lucas 28 amp competition dynamo, Lucas 100/100 watt le Mans headlamps, Lucas SFT foglamps

‘Apart from the body not much different to the production roadster, but Alan Turner certainly got the aerodynamics right.’ And so say all of us, it is a glorious motorcar.


Barrie Bird, many thanks for making contact and contributing both comments and material from your archive for this article

‘Cars for The Connoisseur’, Klemantaski Collection, Inside The Motorsport Paddock (ITMSP), Autocar, ‘The Cobra-Ferrari Wars’ Michael Schoen, ‘Cobra: The First 40 Years’ Trevor Legate, Just a Car Guy, MotorSport

Tailpiece: Thames Ditton, AC men admire their handiwork pre Le Mans, simply superb looking machine…

(Just a Car Guy)





















Iso Grifo A3/C Chevrolet at rest. Piero Drogo’s Carrozzeria Sports Cars, Modena, Italy December 1964…

Renzo Rivolta was an ingenious Italian entrepreneur in postwar Italy.

He owned the Isothermos heater and refrigeration company and postwar decided to build cars, his passion. He started with motorcycles and then introduced the Isetta, an incredibly successful economy car he subsequently and very profitably  licensed to BMW and others.

Into the early sixties he formed Iso Automobili and introduced the Iso Rivolta GT to rave reviews at the 1962 Turin Auto Salon.


The Iso Rivolta GT being driven the way it’s creators intended on the roads outside LA in August 1966 during this road test (Darryl Norenberg)

One of Rivolta’s key players in his nascent enterprise was Giotto Bizzarrini, the gifted engineer who played a key role in the development of the Ferrari Testa Rossa and 250 GTO. After the so-called ‘Palace Revolution’ of 1962, Bizzarrini left Maranello with Carlo Chiti and others and soon found work as a freelance engineer, then with Iso. There, Bizzarrini worked with Iso’s chief technician Pierluigi Raggi to develop the sophisticated platform type chassis which formed the basis of the 2+2 Iso Rivolta GT.


Berney/Noblet Iso Grifo A3/C on its way to 14th place at Le Mans 22 June 1964. Car behind the Dumay/von Ophem Ferrari 250LM 16th (Getty)

Bizzarrini, Bertone and others encouraged Rivolta to build a sports car to enhance sales of the Rivolta, which were flagging, partly due, its said, to the failure of the US importer to meet its contractual obligations. The result was the Iso Grifo two seater GT built on a shortened Rivolta chassis.


Grifo Lusso on Bertone’s stand at the 1963 Turin Salon, and doesn’t it look just so sweet in a brutal kinda way. The alloy wheels are Borrani’s (GP Library)

The chassis had a fabricated sheet steel platform as a base with tubular ‘space frame’ upper sections clearly shown in the photographs below. Two Iso Grifo versions were built and shown at the Turin show in November 1963. The luxury touring ‘Stradale’ A3/L (Lusso) was displayed on coachbuilder Bertone’s stand, while Bizzarrini’s race-prepped A3/C (Corsa) was long, low and lean on Iso’s stand.


Chassis as per text; platform type lower sections and cockpit bulkhead with tubular steel spaceframe otherwise, December 1964 (Klemantaski)


Wearing lightweight aluminum coachwork penned by Bertone’s great and immaculately credentialled Giorgietto Giugiaro, and built by Piero Drogo’s Carrozzeria Sports Cars in Modena, the A3/C ‘was a spectacular vision with aerodynamic flair. The result was an impossibly low and wide car that was exotically curved from every angle’. Some regard the car as one of the most beautiful shapes Giugiaro ever created.

In an effort to avoid the cost, time and complications of engine construction, Iso specified a 5.3 litre Chev V8 engine which was highly tuned for racing in the A3/C. Depending upon specification the famous Chevy 90 degree, cast iron, push-rod OHV ‘small block’ V8 produced between 350 and 420 bhp. The latter spec involved steel internals, roller-rocker valve gear, 4 Webers and the rest, the car good for circa 180mph down the Mulsanne. In addition the engine was placed far behind the front axle, giving the car a very racey front but mid-engined layout that plonked all the masses right where they needed to be. The engine was mounted so far back in the chassis that the Chevy’s distributor, famously, had to be accessed through a removable panel in the top of the dashboard!

The gearbox was a 4 speed Borg Warner T4.

According to some historians, Bizzarrini described the A3/C as the second coming of his GTO, a more refined one at that.


Carozzeria Sports Cars May 1965, note the full race Chevy topped by four side draft 58mm Webers on crossover manifold (Klemantaski)

Suspension of the car was conventional upper and lower wishbones up front with coil spring/damper units and an adjustable roll bar. At the rear a de Dion rear axle was located by twin radius rods and a Watts linkage,  again with coil spring/dampers.

Burmann recirculating ball steering, 4 wheel disc brakes and lightweight magnesium alloy wheels (7X15inch/9X15inch wheels) completed a beautifully specified and integrated package.

The car was 4369mm long, 1730mm wide, 1135mm high, had a wheelbase of 2451mm, a track of 1410/1435mm front/rear and weighed circa 1000Kg

Bizzarrini provided full build execution for the AC/3 at his Autostar Works factory in Livorno, for 18 months Giotto built the car under agreement with Iso. Iso and Bertone produced the Grifo A3/L road car.

To Rivolta the Grifo was a tool to promote his GT car, but Bizzarrini was a racer to the core so fissures developed in the relationship between the two men as to where the primary focus should be. After about 20 examples of the Drogo-bodied A3/C’s were made, in the summer of 1965, Bizzarrini left Iso and produced the model under his own name, in both Strada and Corsa forms. As few as 115 examples of the cars were made under both names.

Most of the cars pictured in this article are some of the 20 A3/C coupes built using very lightweight, riveted (over 7000 of them were utilised in each body) aluminium bodies fabricated by Piero Drogo’s Carozzeria Sports Auto, the photos were taken in Drogo’s workshop in Modena in December 1964 and early 1965.

Part of the A3/C’s transition from an Iso to a Bizzarrini involved a change of coachbuilders from Drogo to Salvatore Diomante and his Carbondio concern, which was eventually reborn as Autocostruzione SD of Torino.


The Pierre Noblet/Edgar Berney Grifo ahead of the #5 Dan Gurney/Bob Bondurant Shelby Cobra Daytona Coupe 4th with the nose of the #24 Lucien Bianchi/Jean Blaton Ferrari 250GTO 5th during Le Mans 1964 (Getty)

From a racing perspective amongst the cars best international results are 14th outright and 4th in class at Le Mans in 1964, 5th in the Monza 1000Km and 19th at the Nurburgring 1000Km in 1965 a season which started badly with one car destroyed at Sebring and then another at Daytona.

Given the cars low build numbers it raced as a prototype against outright class mid-engined sports-prototypes rather than amongst the GT cars more akin to the Grifo in specification.


Bonhams, Sotheby’s, Getty Images, Klemantaski Collection. Darryl Norenberg/The Enthusiast Network, The GP Library, F2 Register



The Getty caption describes this car as a Lusso, outside Drogo’s workshop in December 1964, same chassis as the opening photo (Klemantaski)

Tailpiece: A car fit for a King. John Lennon susses the interior of his new Iso Fidia S4 at Earls Court in October 1967…