again sent no works Group 6 cars, in order to not compete against their many customers in their 935Group 5 cars. The lone Group 6 Porsche, a Martini Racing-sponsored roadster entered by Joest Racing for Reinhold Joest himself and Jacky Ickx, was christened the Porsche 908/80 by the team, but looked much like the 1977 version of the 936. For a long time the car was believed to be a hack on a 908 chassis until it was discovered that it was in fact built on a real 936 replacement chassis, the 936-004. As Porsche didn't wish to be in the business of selling 936s to customers, the secret was kept by using a 908 chassis number plate. The 908/80 was favorite but Porsche could also count on many 935, five Group 5 plus eight IMSA GTX, including three cars from the Sebring-winning Dick Barbour team. Most of the opposition was in the GTP class: three WM-Peugeot and a trio of local heroes, the Le Mans-built Rondeau-Cosworth.
Race
The start was the probably wettest ever at Le Mans. Ickx laid back in his roadster until he could actually see something else other than the fog created by closed-cabin cars: Porsche 935s, BMW M1s and Rondeau coupes. John Fitzpatrick was leading with Dick Barbour's Porsche 935. Hans Stuck had shoved his BMW M1 from 26th to second by 17:00. At that time Jean Rondeau had two of his made-in-Le Mans cars in the top 10. When the rain decreased Ickx and Joest picked off one car after another. By the end of the third hour, Joest found himself in the lead. When Ickx was back in the car he broke the fuel injection pump belt. But Joest had planned wisely; there was a set of basic tools and a spare belt in the car. Ickx restarted just 14 minutes later but this was enough to lose the lead. At nightfall, a Rondeau was leading the race but Ickx began the chase. By 01:00 Sunday, the 908/80 was on the same lap as the leaders. Two hours later, they were ahead and began to leave the French coupé behind. After numerous lead changes caused by refuelings and scheduled maintenance on the cars around 07:00, the Joest Martini Porsche had built a solid lead. But the Joest team had underestimated the Rondeaus, as they didn't expect the Cosworth to be very reliable. As a result, Joest and Ickx did not run fast enough and at 10:00 when the 908/80 had a gearbox failure, like the works 936s in 1977, they had not built up a large enough lead. The Rondeau of Jean Rondeau himself and Jean-Pierre Jaussaud gained the lead with a gap of three laps over the second placed car. Ickx had to begin a third chase. When Jaussaud took over from Rondeau with an hour and a half remaining, the Rondeau had still a two laps advance but the Porsche was running faster. With 35 minutes left to race, the rain returned. Ickx pitted for wet tyres while Jaussaud kept the slicks. Jaussaud had made the right choice and remained in the lead. However, there was a final surprise: As the rain became heavier in the last lap, Jaussaud lost the control of his car. By luck he did not hit anything. For the first time a driver had won Le Mans on a car bearing his own name. At the end of the race Ickx announced his retirement, which he was to reverse a few months later.