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One chassis, Five Le Mans

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[1]

Page 134, October 2010

It wasn’t a 24 Hours winner, but Gulf GR8 chassis ‘802’ was one of the race’s most successful cars in terms of longevity

The list of history’s great winning Le Mans cars is probably headed by those chassis which won more than once. Ford GT40 ‘1075’ immediately springs to mind, the Gulf-JW team’s 1968-69 double winner, together with Reinhold Joest’s ‘New Man’ Porsche 956 ‘117’ which did the double in 1984-85. Rolling further back the works Bentley Speed Six ‘Old No 1’ – registration ‘LB 2332’, chassis ‘MT3464’ – scored its back-to-back victories in 1929-30. Any twice-winning Le Mans 24 Hours car occupies a very special ledge on the cliff face of desirability, but there are more which returned to the Sarthe and achieved really significant finishes there without actually winning outright.

Consider for a moment the case of Gulf GR8 chassis ‘802’. This projectile first appeared with Cosworth-Ford V8 power at the Sarthe for the 1975 24 Hours. It was run by the former Gulf-JW team restyled as Gulf Research Racing but retaining the hallowed old pale blue/orange livery. Vern Schuppan/Jean-Pierre Jaussaud drove ‘802’ home third that year. The Gulf programme was then taken over by Harley Cluxton’s well-known Grand Touring Cars Inc operation from Scottsdale, Arizona. He revived the old Gulf-JW ‘Mirage’ name, and ‘802’ with restyled bodywork finished in GTC livery was co-driven at Le Mans in 1976 by Jean-Louis Lafosse/François Migault to finish second.

As if this would not be sufficient race history for any modern classic, ‘802’ then finished second again at Le Mans in 1977 when Vern Schuppan/Jean-Pierre Jarier drove the old lady, which had been re-equipped with a turbocharged Renault V6 engine. Still Cluxton, that most engaging and genial entrant/enthusiast, soldiered on with ‘802’, entering it yet again for Le Mans in 1978. That time it finished 10th, co-driven by Vern Schuppan/Jacques Laffite/Sam Posey.

So that was four Le Mans races down, and still one to go. Back at the Sarthe circuit for the fifth time in 1979, reconverted to Cosworth-Ford V8 power, chassis ‘802’ – shared by Schuppan/David Hobbs/Jean-Pierre Jaussaud – for the first time failed to finish.

During this extraordinary career, ‘802’ was variously titled as the Gulf-GR8 (1975), Mirage-Ford M8 (1976), Mirage-Renault M8 (1977), Mirage-Renault M9 (1978) and Ford M10 (1979). What was it that Bill Boddy and Jenks used to bewail regularly here in Motor Sport – “Pity the poor historian”? Yet despite all the specification and shape and livery changes to ‘802’, beneath the skin it was all essentially the same individual chassis structure, eventually sold to German collector Peter Kaus, displayed within his Rosso Bianco Collection in GR8 form, and recently offered in the Bonhams auction sale at Quail Lodge during the Monterey Historics weekend.

John Horsman, the Gulf and later GTC team’s technical director responsible for ‘802’, recalls: “For Le Mans ’75 we wanted a longer body to reduce drag and the designer Len Bailey drew a new chassis with a six-inch longer wheelbase, giving more room for things like oil tanks. JW and I sketched the body shape, and our machinist, Brian Holland, made a quarter-scale clay body shape to the sketch. We made a few minor changes before the model was sent to FKS Fiberglass in Poole who made the panels.

“Despite a rather large frontal area the GR8 was a pretty good shape, with a low drag coefficient and (for its day) good downforce from the rear wing. It was a good car for Le Mans, easy to drive, with no vices. We had modified various areas to lower the fuel consumption to meet Le Mans’ required minimum 20-lap distance between refuelling stops. In fact we went too far as the car could do 22 laps, but it’s nice to have a safety cushion in a 24-hour race.”

John recalls the Cosworth DFV engine’s notorious vibration as having been the worst threat: “It had been designed as an integral chassis member for Formula 1, forming the rear half of the car structure. But, from our original Mirage M6, Len Bailey wisely included three-tube braces along each side. Over 24 hours the DFV’s inherent vibration was very destructive. At Le Mans in 1975 it fractured the engine’s lower mounting blocks, putting all the rear-end load onto Len’s tripod frames on each side. This light steel framework then held both our cars together during the last half of the race. Otherwise they would literally have collapsed in half like a torpedoed ship! This lower mounting was remade in steel for the ’76 race and both cars finished without trouble in that area.

“Built to resist Cosworth vibration, the Gulf Mirage GR7 had been overweight – the lightest we ever got it was 720kg with a lot of titanium parts, but with a second alternator for Le Mans. The minimum weight limit then was 650kg, which is what the Matras managed with their vibration-free V12 engines. The extra wheelbase of the GR8 made it even heavier than the GR7, but the DFV engine’s vibrations were irresistible. No sooner would we overcome metal failures in one area than the vibrations found another area to destroy! For instance, small body clamps as used by Matra and Ferrari with their smooth 12-cylinder engines stood no chance on a DFV V8 car. In the 1975 race DFV vibrations also broke an exhaust pipe on our leading car, ‘801’, despite more reinforcement there. We changed it without losing the lead, but the failure shortened it to only one lap. Yet overall the GR8 was a good car for Le Mans…”

Interesting sidelights on such a successful Le Mans car – in some respects, during its early Cosworth-engined days, perhaps victorious despite its engine, rather than because of it.

Gulf wins "economy" Le Mans

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[2] Page 27, July 1975

Gulf wins "economy" Le Mans

The combination of a fuel-consumption formula (all the cars had to run for 20 laps or more without refuelling), the absence of many graded drivers, and—worst—the lack of Matra, Alpine, Ferrari or Alfa Romeo prototypes, all combined to make this year's Vingt-Quatre Heures du Mans decidedly a non-event, and the spectators reacted by staying away in their thousands. Victory always seemed within reach of the two well-prepared Gulf Research Racing GR8s, which took turns at leading the race, and on Sunday afternoon the achievement was recorded by Derek Bell and Jacky Ickx. The second car had been delayed with alternator problems, and then by a fault in the differential, and finished in third place behind the Ligier-Ford DFV driven by Jean-Louis Lafosse and Guy Chasseuil.

The Automobile Club de l'Ouest seemed to be in trouble from the very beginning. First they introduced the fuel-consumption formula, virtually dictating a 25% improvement in consumption to the 3-litre teams. Then, having been banished by the CSI from the World Championship for Makes, the ACO had to cancel the vital test weekend because the CSI introduced a clashing sports-car race to the calendar. And when the final entry list was published, it showed a heavy preponderance of Porsche 911 Carreras, which filled no fewer than 28 of the 55 starting places—just over 50% of the total. Just where endurance racing would be now if Dr. Porsche had not founded his own car company is hard to imagine, for with four more Stuttgart cars in the 3-litre prototype class the company was better represented than ever before!

Gulf calculated that they would have to detune their engines to 370 horsepower (at 8,000 r.p.m.) to achieve 7.5 m.p.g., though during practice they found that their calculations were over-cautious and that the GR8s driven by Bell/Ickx and Vern Schuppan/Jean-Pierre Jaussaud were returning about 8.5 m.p.g,, and could run 25 laps if necessary without topping up. Just as well for Guy Ligier, who detuned his DFV engines to 410 horsepower to counteract the heavy weight of the GT bodies on his JS2 models driven by Lafosse, Chasseuil, and Henri Pescarolo and Francois Migault. Another fancied runner was the 3-litre V6 Maserati-powered JS2 (a development of the road car) driven by Jean-Pierre Beltoise/Jean-Pierre Jarier. Private entry hopes were kept high by Alain de Cadenet's Lola-DFV shared with Chris Craft, and the dark horses of the event were the old Porsche 908/3s (which never did develop more than 360 b.h.p. anyway), of which the Reinhold Joest/Mario Casoni/Jurgen Barth entry was easily the most effective.

Speeds were on average 15 sec. per lap slower than last year's, and though visually that mattered little it did detract somewhat from the glamour of the event. The two Gulfs, fastest in practice, soon settled into a four-minute-per-lap rhythm at the head of the field, with the Ligiers, Craft's Lola and Joest's Porsche 908 in pursuit, none of them hurrying particularly and the drivers audibly taking care of the clutches and gearboxes as they accelerated past the pits. After an hour Schuppan led Bell by 14 sec., followed by Joest, Craft and Pescarolo, with Marie-Claude Beaumont's 2-litre Alpine V6 in sixth place. Half an hour later Mlle. Beaumont became the first, and only, casualty of the fuel-consumption limit when the French car coasted to a standstill half way round its 21st lap.

After the first refuelling stops Ickx and Bell firmly established themselves in the lead, which they never relinquished although their command became tenuous on Sunday morning when the car was delayed 12 min. by a broken exhaust pipe, letting Lafosse's Ligier move briefly on to the same lap. The Schuppan/Jaussaud Gulf was comfortably second until, late on Saturday evening, the alternator failed and half-an-hour was lost in the pits.

In the hours of darkness Alain de Cadenet's Lola lost its rear body section along the Mulsanne Straight, and Migault's Ligier ran over the bits at high speed, damaging its nose section. Both cars were considerably delayed while they were patched up, de Cadenet eventually finishing down in 15th place and Migault/Pescarolo retiring when a puncture put them even lower down the order. Beltoise crashed the Ligier-Maserati heavily after colliding with a Ferrari Daytona, but Lafosse and Chasseuil had no trouble with their car and kept the pressure on the Gulf team all the way to the end.—M.L.C.


http://www.racingsportscars.com/chassis/photo/GR8__802.html http://www.duncanhamilton.com/cars-for-sale/mirage-gr8-chassis-802/ https://www.bonhams.com/auctions/14261/lot/222/


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