The Silverstone Six Hours

Silverstone, May 14th

Spectators who went to Silverstone on May 14th to watch the BRDC’s fourth round of the World Championship for Makes probably thought they were getting a motor race for their money. After all, the Silverstone Six Hours was pitching Porsche’s and BMW’s works cars against each other for the first time this year, and the supporting cast of Gp 5 machinery was as good as you were likely to see outside Le Man’s. In a sense, the spectators were right. But in another sense, they were wrong. “We’re not really here to win this race, so much as to gain some race experience before Le Mans,” explained Porsche’s Manfred Jantke, contemplating his team’s brand new Gp 5 car, resplendent in Martini colours and never raced before. So there we had it: the fastest car in the entry by a mile and half, designated the 935/78, driven by Jochen Mass and Jacky lckx, powered by a 3.2-litre flat-six engine that produced upwards of 750-b.h.p. with the aid of twin turbochargers, capable of attaining 185 m.p.h. even on Silverstone’s not particularly lengthy Hangar Straight. And it was all there for a sort of flagwaving, extended test session, in effect.

Not that the new Porsche went badly for a test session. In unofficial practice Mass lopped five whole seconds off his own Group 5 lap record, in first practice he was easily the quickest, in second practice Ickx went faster still to confirm the car’s pole position, and in the race itself they led every inch of the way to win by seven laps. So fast was the car that Mass pulled out a staggering four second advantage over everyone else on the first lap, and from a rolling start at that! It really had no opposition at all, and one wonders how fast the Porsche might have gone if victory had been its first priority!

Behind the works Porsche, however, there was quite a good race for second place. Interest was added by a shower half an hour before the start, which forced everyone to start on rain tyres and then change to slicks after only a few laps. In the end, it was the Kremer brothers’ “customer” Porsche 935, a 77A model, that came home second, driven by Frenchmen Bob Wollek and Henri Pescarolo. They gained that second place only after a spirited tussle in the race’s middle stages with all three of Georg Loos’s similar 935/77As and the single works BMW 320 Turbo.

From their record so far this season, BMW cannot have gone to Silverstone in too optimistic a mood, and even with Ronnie Peterson at the wheel their 2-litre Turbo lay only seventh in the opening laps. Gradually it moved up the order, climbing to second place despite a fuel injection fault that once resulted in its almost running out of petrol well before a refuelling stop was due. Eventually it ran tOr virtually four hours, the best a BMW Turbo has ever managed in a European race; then the differential overheated and failed after a suspected break-down of the rear axle’s lubrication system.

For Georg Loos, Silverstone was little short of a disaster. He had entered all three of his Porsche 9355, although employing only live drivers: John Fitzpatrick, Derek Bell, Toine Hezemans, Klaus Ludwig and Hans Heyer. That ensured some very complicated driver switching arrangements, which might have explained why his team’s pit stops seemed less smooth than usual. All three cart held second place at one time or another, but in the end Hezemans crashed one into the bank at Abbey after a light shower had made the track ultra-slippery. The second car dropped out when a wheel nut jammed and refused to budge during a routine pit stop, and the third retired 75 minutes from the finish when a sealing ring between engine and gearbox let all the oil out.

The other quick, privately entered Porsche 935s fared little better. In a remarkable coincidence, both the cars of Finotto/Facetti and Lafosse/Leclere lost front wheels within seconds of each other after that first, unscheduled round of tyre changes when the track dried out soon after the start. The car of Konrad and Merl lost half an hour when a driveshaft broke, but fought back gamely to sixth place at the finish, while the Porsche of Haldi and Mueller retired with extensive front and body damage after its second accident of the race.

As for the quintet of 2-litre, normally aspirated BMW 320is entered, it was rather a case of all or nothing. Three of them crashed, but the two survivors fought out the class lead and third place overall to the last lap, the Belgian car of Grohs and Joosen pipping the Swiss entry of Kottulinsky and Hotz by only 15 seconds. Harald Grohs in particular produced an inspired if sometimes untidy performance, and slowed only when both corners of his car’s front spoiler had been broken off. Of the other three 320s, Dieter Quester crashed his at Stowe before the end of first practice, Bo Emanuelsson damaged his at the same corner early in the race, and Umberto Grano put the car he shared with Giorgio Francia into the fences at Becketts on his second excursion of the event. J.C.T.