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Porsche: Excellence Was Expected

by Karl Ludvigsen

Excerpt from Chapter 34, Volume 2

24 Hours and 500 Miles 1977-1981

In one of the most dramatic Le Mans races in history, Jacky Ickx, Jürgen Barth and Hurley Haywood battled back from a hopeless position to win the 1977 edition of the 24-hour race with Porsche"s 936.

If Porsche lacked competition in Group 5 racing at the end of the 1970s, the same was decidedly not the case in Group 6. There France"s state-owned car company, Renault, had staked its claim. Renault had acquired the Alpine sports car company in Dieppe, where it developed tube-framed sports-racers powered by turbocharged V-6 engines. Against Alpine-Renault and Alfa Romeo, Porsche had taken the world sports car championship in 1976 with its 936-a car it had "improvised," said Ernst Fuhrmann, "just to stop others from having it too easy." In 1977 it decided not to compete in the full series but instead to concentrate on defending its title at Le Mans.

A clear focus on Le Mans at the expense of the other Group 6 races meant that the 936"s design could be further optimized for the special conditions of the Sarthe circuit. A major step was the narrowing of the car"s track by 40 mm (1.6 inches) at both ends by fitting shorter suspension wishbones. This enabled the flanks to be drawn in, making a major contribution to a reduction in the car"s frontal area from 18.8 to 17.8 square feet.

Final refinements were made to the aerodynamics in Volkswagen"s wind tunnel in February 1977. These included confirmation of the drag-reduction value of higher cockpit sides, a tweak that had been evaluated but not used for 1976. In an echo of experiments with the 1962 Grand Prix Porsche, the engineers tested flat discs covering the wheels, but these made no difference to the drag. A lengthening of the tail helped bring the drag coefficient down from 0.398 to 0.370 while maintaining downforce, which at speed was 234 pounds at the front and 670 pounds at the rear. In all, the revised car"s drag was nine percent less than the 1976 version, which contributed to an improvement of 16 mph in its top speed as measured in tests at Paul Ricard.

Porsche optimized its 936 for the 1977 running of Le Mans with reduced frontal area, a lower drag factor and twin turbos instead of the single unit used in 1976.

While the 1976 936 had fed its 2.1-liter 12-valve engine with a single turbo-charger, the 1977 version was pressurized by two smaller KKK units, which gave better throttle response thanks to their lower inertia. The turbos were mounted far back in the car"s long tail with a single large Porsche wastegate between them. The exhaust system proper was simpler with this arrangement, while long tracts forward were needed to deliver pressure air to a single large transverse intercooler placed just aft of the cooling fan. Boost was set at 19 p.s.i. for the race. On the 22 p.s.i. boost used during practice, the engine developed 540 bhp at 8,000 rpm and peak torque of 362 lb-ft at 6,000 rpm. With this power the 936 was timed at a top speed of 217 mph at Le Mans.

Incredible 1977 Le Mans
After extensive tests of one car at the Paul Ricard circuit in March that included a successful 28-hour durability run, two 936s were prepared for the Le Mans 24 Hours; one weighed 1,615 pounds and the other 1,628. On average this was 26 pounds heavier than the two 1976 cars had been, not including the radio and the tools that the cars always carried to help the driver make repairs out on the circuit. The white cars now carried their red and blue Martini Racing striping atop the fenders instead of down the center of the body as the year before. Among their rivals they faced three works Alpine-Renaults and two American-entered Mirages powered by Renault engines.

"The race developed very dramatically," said Hans Mezger. "Three hours after the start it seemed that the result was already decided. At that time no one believed that Porsche would still be able to win this race." About an hour into the race, half-way through his first driving stint, Jürgen Barth brought his 936 into the pit and declared that his engine had lost power. After the fault was traced to the injection pump this was replaced, causing a stop of 28 minutes and 50 seconds. A later autopsy of the pump disclosed the failure of a circlip only 4 mm in diameter that affected the lever that controlled the unit"s delivery pressure. It was the first time this failure had occurred.

While poor Barth resumed his race in 41st place, the sister Porsche shared by Ickx and Pescarolo was well forward until, just three hours into the race, it broke a connecting rod and retired. Subsequent analysis disclosed that the surface of the titanium rod had not been polished enough to remove all the stress-raisers-a process even more critical with titanium than with steel. At this point it was obvious that the race was decided in favor of the Alpine-Renaults, three of which were cruising in the lead.

Work was beginning here on removing the air-cooled 1977 engine from the 936 in preparing for the installation of its new 24-valve unit of 2,120 cc, at upper right.

However, for Porsche chief Ernst Fuhrmann, the outcome was not foreordained. When at the 4½-hour point Hurley Haywood brought in the remaining 936 for a routine driver change and refueling it was up to 15th place, nine laps behind the leader. Fuhrmann installed Jacky Ickx behind its steering wheel and gave him the explicit command, "Win or bust!" The latter seemed the most likely result, but Ickx accepted a challenge that Hans Mezger called "almost hopeless." In an epic drive that included two four-hour stints, the Belgian lapped at record speeds, seven to ten seconds faster than his co-drivers. In the process, he lost 18 pounds of body mass.

By the sixth hour the 936 was back up to sixth place and by the ninth it was up to fourth place. At 5 o"clock in the morning, after 13 hours, it was second but still 7½ laps behind the leading Alpine-Renault. A runner-up finish was the likely outcome, worthy in the circumstances. But just as dawn was breaking, the leader retired with an engine failure and the Porsche was in front. It had a margin of only a lap over the next Alpine-Renault but at noon, with four hours" racing remaining, this too broke-leaving the 936 unchallenged.

The drama of 1977 was not yet ended. With 40 minutes of the 24 hours remaining the dismayed Porsche pit staff saw a gout of smoke from the 936 at the Ford Chicane just before the pits. Hurley Haywood drove it straight into the pit lane. While mechanics worked on the car he and his team-mates were reassured that no competitor had a chance to cover as much distance as theirs had. But one more Le Mans ritual had to be satisfied. This required that a car cross the line under its own power and that its last lap be completed in no more than 15 minutes.

The piston in cylinder number three had seized. That cylinder"s spark plug was removed and its fuel injection deactivated. But many questions remained, as Norbert Singer related: "How serious was the piston seizure? Would the engine start again, and if it would, how long would it run? We were preoccupied by all these questions when Jürgen Barth took the wheel for the last two laps. And it worked!"

A major change in the 936 for 1978 was the addition of long NACA inlets at the sides, delivering air to the radiators for the water-cooled cylinder heads.

With Barth at the wheel, Porsche chassis 936.001 successfully did the necessary and was flagged home the winner at Le Mans. During its 20 stops the car had been at rest in the pits for one hour and 31 minutes. Barth had driven for eight hours and 40 minutes, Haywood for three hours and 12 minutes and Ickx for 10 hours and 37 minutes. If ever perseverance and skill were rewarded, this was such an occasion. Justly, Jacky Ickx was the star when the Porsche was celebrated in the Stuttgart town square on its triumphant return to Germany.

The 936"s piston failure had been one of the breakdowns that encouraged the creation of the new 24-valve engine with its liquid-cooled heads. In its 2,120 cc version (87 x 60 mm) it was installed in the 936 for yet another Le Mans sally in 1978. The two cars looked and were much the same as before, with the exception of large NACA-duct inlets in their flanks to feed air to the radiators cooling the respective cylinder heads. To make room for the radiators and also for slightly larger rear tires, the rear wheels were moved back by a bit more than an inch to make the wheelbase 2,430 mm or 95.7 inches. This required longer trailing suspension radius rods.

A peculiar-looking new rear wing, developed in cooperation with aerospace firm Dornier, had drooping side plates that made its downforce less sensitive to side winds. This was balanced by a new nose that was four inches longer. Paul Frère estimated the Cd of the 1978 version of the 936 as 0.40, similar to the 1976 version but not so good as the 1977 body. With the extra valves and liquid cooling the cars were also heavier, Frère said, at 1,769 and 1,778 pounds. Neither weight nor drag was calculated to show to best advantage the output of the new engine, which developed 545 bhp on a boost of 20 p.s.i. at 8,500 rpm-a subtle improvement over its predecessor.

Rivalry with Renault
Three 936s were readied for Le Mans 1978, one of which was a brand-new chassis. One of the old cars was equipped with the 12-valve engine as raced in 1977. Although delayed by a 13-minute stop to fit a new left-hand turbocharger the 12-valve car finished third, driven by Peter Gregg, Hurley Haywood and Reinhold Joest. During practice, the boost of the new engines was turned up to 24½ p.s.i., lifting their output to 640 bhp at 8,400 rpm and producing torque just on 400 lb-ft at 6,450 rpm. This allowed the best Porsche to qualify just ahead of the best Alpine-Renault. In spite of their 1977 debacle the French were back at Le Mans again.

A hasty effort to prepare two 936/78s for Le Mans in 1979 resulted in one retirement and one disqualification. High-flying Essex Petroleum was the sponsor.

In the race, however, the Alpines were able to race much closer to their qualifying paces than the Porsches. Ickx was an embarrassing 11 seconds behind the leading Alpine after his first lap, and on his second he called at the pits for a check of a throttle-pedal return that was too slow-not a good feature of a turbocharged racing car. This sorted by the removal of an auxiliary fuel-pressure pump, his car continued until at dusk it broke a fifth-gear pinion which had had lightening holes drilled larger than specified.

Playing musical chairs with their drivers, Fuhrmann, Bott and Jantke moved Ickx to the other car. From its crew Jochen Mass took over Ickx"s seat, with Pescarolo, after the gearbox was repaired. Given the green light to raise the boost to qualifying level, this crew returned to the fray. Over the next 12 hours they improved their position until the car was terminally retired when Mass left the road.

In the meantime Ickx was making good time as he had in 1977. He was well paired with Frenchman Bob Wollek, who matched his speed. One Alpine-Renault held the lead, but this obligingly retired six hours from the finish, which left the 936/78 out in front. But it, too, was stricken by a broken fifth gear that required a 37-minute pit stop to repair. Delayed to fourth, the drivers were allowed to use the qualifying boost that the other car"s 24-valve engine had tolerated for half a day. They finally finished second behind the only Alpine-Renault that had enjoyed an untroubled race.

"Had Renault not won," wrote Paul Frère afterward, "it would have been a humiliation for France and certainly a catastrophe for all those responsible for the cars and the Le Mans operation. For Porsche, whose cars were winning races and rallies on every weekend all over the world, who already had the world championship of makes in their pocket and who make it all look so easy that their merits barely get proper recognition, this was just a lost battle. The defeat the Porsches suffered at Le Mans was more than honorable and, considering all the implications, it was probably as well that they lost."

Noble and valid though this assessment was, Porsche was not in a position to be as philosophical about the result of its 1979 Le Mans entry with two 936s. The only saving grace of this event was that it was won by the Kremer-entered 935 K3. In fact, Porsche had not planned on entering at all but had been persuaded at the eleventh hour to prepare a brace of 936/78s under the sponsorship of David Thieme"s Essex Petroleum. Flying high at the time on the boom in oil prices, the flamboyant Thieme was the backer of Colin Chapman"s Formula 1 Lotuses.

One car was entered for the Silverstone race as a precursor to Le Mans in 1979. This revealed a problem with the tires turning on the rims that contributed to another 936 crash for Jochen Mass. The same problem cropped up in the fast Dunlop Curve at Le Mans for Brian Redman in the car he was sharing with Ickx. Massive damage to the car"s left rear quarter caused by the resulting tire failure took more than an hour to repair. Jacky"s attempt to stage another of his patented comebacks was frustrated by a broken injection-pump drive belt and disqualification following outside assistance. Wollek and Haywood in the sister car reached third place but engine problems ended their race.

The formula of a Porsche turbo engine in a light and open sports-racing chassis was by this time obviously attractive to the private teams racing Porsche hardware. One such team, that of Reinhold Joest, succeeded in persuading Porsche to make one of its 936/78 racers available to it for the 1980 Le Mans race. Porsche tried to downplay its involvement in the entry, but the presence of Jacky Ickx as co-driver tended to belie its denials. With the return of Martini backing, their effort was a good one, holding the lead in the fourth and fifth hours, but was frustrated again by the failure of fifth gear. After repairs they finished second behind a Rondeau-Ford.

In 1980 a 936 built by Reinhold Joest from Porsche parts was driven by himself and Jacky Ickx to second at Le Mans, finishing two laps behind a Rondeau-Ford like the one following Ickx.

Those who could not aspire to a works 936 built their own. Privateers bought up old Porsche 908 chassis, which easily accommodated a suitable flat-six turbo. With the help of the works service department these could be converted into highly convincing facsimiles of the factory cars. Such cars, known as 908/80s, carried on through the end of the Group 6 era in 1981 and, further modified, into 1982"s Group C racing.

Exploring the Brickyard
If Porsche"s own efforts in Groups 5 and 6 had tapered off noticeably after Le Mans in 1978, there were valid reasons for this. Porsche had been seduced by the undeniable appeal of the Indianapolis 500-mile race. With its strong North American sales, Porsche could hardly ignore the attraction of an historic event that monopolized the attention of America"s racing enthusiasts for the entire month of May. Jo Hoppen, Porsche"s racing representative in the States, had lobbied strongly for participation at Indy-not necessarily with a car, but certainly with an engine.

A small but influential delegation from Weissach and Zuffenhausen arrived in Indiana in mid-May 1977 to have a first-hand look at this phenomenon. Accompanied by Jo Hoppen, Manfred Jantke and Helmut Flegl flew to Indianapolis. Jantke was the Porsche public relations and sports director, while Flegl was an engineer whose curriculum vitae included the Can-Am 917, the 936 and the 928 road car. Their putative link with the Speedway doings was the sponsorship of USAC"s Mini-Indy series for Super Vee cars by VW of America, which was then importing Porsche cars. USAC arranged convenient accommodation for the Porsche men and placed a motorcycle at their disposal for the commute to the track.

In Gasoline Alley the trio were taken under the wing of Leo Mehl, the gregarious and popular Goodyear racing chief. Any effort to keep their presence low-key was doomed to failure. Word quickly spread that Porsche people were at the Speedway. Anthony Joseph Foyt, already a legendary three-time winner of the 500, did not beat around the bush. "What are you doing here?" he asked the delegates. To their response that they were just having a look around he asked, "Are you going to come?" When they protested that they didn"t know if they would, Foyt looked Flegl in the eye and said, "You come, we race you!"

This made a strong impression. So too, in a way, did the race. Tom Sneva qualified for pole at 198.880 mph in a Penske McLaren-Cosworth, one of four Cosworth-powered cars to make the 33-car field. Sneva finished second behind none other than A. J. Foyt, who collected his unprecedented fourth win at the Speedway. Another Cosworth-powered car placed third ahead of a shoal of Offy-powered racers.

"It"s an endurance race," said Jantke afterward. "Actually, it"s kind of boring." "Foyt has won here four times," added Flegl. "Now it"s time that we came here." He was willing to accept Foyt"s challenge. But what would be the view of his superiors in Germany?

Indy regulars were very leery of the potential of a Porsche entry. Their views were reflected by a McLaren mechanic who, well recalling the impact of Porsche on the Can-Am series, said, "If Porsche comes, all the others can pack up." Nor did the surfacing of Porsche personnel in an otherwise quiet Indiana city go unnoticed by the American press, which immediately began speculating about a Porsche Indy entry in 1978. Jo Hoppen did little to discourage this by saying, "For us, it would be harder than anyone else to build an Indy car. For anyone else, they would take the best engine, the best transmission and the best brakes and then build a chassis around them. We"ve got to do it the Porsche way." Jo"s words would have a certain echo in a Porsche venture a decade later. But for now Porsche was actually considering only the supply of a suitable engine, not building a complete car.

This was not the first time that Porsche had been offered an Indy opportunity. Its Can-Am partner in 1972 and "73, Roger Penske, had been competing at Indianapolis since 1969, when Mark Donohue was rookie of the year. Donohue took time out from his first Porsche 917 Turbo season to win the Indy 500 for Penske in 1972.