The 1991 24 Hours of Le Mans was the 59th Grand Prix of Endurance, taking place at the Circuit de la Sarthe, France, on the 22 and 23 June 1991. It was also the fourth round of the 1991 FIA Sportscar World Championship season.
This was the inaugural season of the new 3.5-litre non-turbo regulations for Sports Cars, however the number of teams entering cars in that class was very limited, so the entry list was opened up to the old Group C category. To promote their new formula, FISA decreed that the top ten grid spots had to be taken by cars in the new class, regardless of their qualifying time, with the Group C cars arranged behind them. The piston-engine Group C cars were penalised to carry 100 kg extra ballast, but the rotary-engine Mazdas were not.
The race was anticipated to be a final showdown between Jaguar and Sauber-Mercedes, with Porsche, Mazda and the new Peugeots playing supporting roles. Indeed, from the front of the grid, the Peugeots did lead for the first hour, but their reliability failed them, and they were soon in the pits to eventually retire. It was then that the Mercedes cars that took up the lead, even running positions 1-2-3 for several hours. The Jaguars were being stymied by fuel consumption and had to temper their pace accordingly. Nevertheless, the three cars stayed in the top-10, fighting with the two new Mazda 787Bs.
By the halfway point, the Schlesser/Mass/Ferté Mercedes were up by a lap over their teammates, the Junior team of Wendlinger/Schumacher/Kreutzpointner, and by three laps over their nearest opponents, the Mazda of Weidler/Herbert/Gachot. Within an hour though, Wendlinger brought his car into the pits stuck in fourth gear. The Mazda was lapping faster than the Mercedes but was unable to make a serious dent in the margin. As the new day dawned, the Jaguars were successively delayed by off-road excursions and engine problems. The leading Joest Porsche had been running as high as fourth but came to a stop out on the track.
After leading for almost 17 hours, the leading Mercedes came into the pits with its temperature skyrocketing. The belt on the waterpump had come off and stopped the engine cooling – a similar issue to what had struck the third team-car a few hours earlier. The damage was terminal, and the Mazda screamed past into the lead with three hours to go. Their run had been very reliable, and although the Jaguars tried to push, Herbert brought home the Mazda to win by two laps over the IMSA-team Jaguar of Jones/Boesel/Ferté. The Mercedes-Junior team lost a place in the last hour but survived to finish fifth and win the Index of Energy Efficiency. Michael Schumacher also set a new lap record, beating the previous one by five seconds. Only 12 cars were classified at the finish, including just a single entry from the new Category 1.
Regulations In the close-season, FISA (Fédération Internationale du Sport Automobile) and the ACO (Automobile Club de l'Ouest) had finally reached an agreement. The ACO accepted their demands over media, commercial and timekeeping rights. In return, FISA offered a five-year contract in the new Sportscar World Championship (SWC), with worldwide TV promotion and coverage.Spurring 2012, pp.58-9
The new sports car regulations dictated non-turbocharged piston engines of 3.5-litres, as were being used in Formula 1 currently. The cars had a minimum weight of 750 kg. Few manufacturers had prepared new models meeting the regulations, so FISA had to let the Group C cars (to be called "Category 2") back in the entry lists and declared 1991 as another "transitional season" to allow more time. They would have the same fuel limit as before (2550 litres), but now had their minimum weight lifted by 100 kg to 1000 kg. However, no such weight limit was applied to the GTP rotaries.Clarke 1999, p.168 Motor Sport Aug 1991Clarke 1999, p.172 Road & Track Oct 1991 They committed 50 entries to the ACO for the race, but by March there were only 17 for the Championship.Clarke 1999, p.153 Autocar Jun 12 1991Clarke 1999, p.154 Autocar Jun 12 1991 FISA reduced their commitment to 40 Championship cars and Le Mans and two non-European rounds were given a waiver to allow non-registered teams to enter. Having not been consulted as required, Jaguar and Mercedes in particular, were livid that Nissan and Toyota (who had abstained from the Championship) would now be able to race after all for the one-off event without the expense of the rest of the series. A compromise was reached at an emergency meeting between FISA and the Championship team managers. Non-registered cars would only be allowed to race at Le Mans if entered by an SWC team and running the same engine as that team. Those teams already in the SWC still had to enter at least one of their Category 1 cars.Williams 2023, p.328 In light of this, the ACO extended the deadline into May, and the entry list swelled accordingly.
In September 1990, the ACO had started demolition and rebuild of the pits complex that had originally been constructed following the 1955 disaster. The lavish new facility, costing more than £12 million, was state-of-the-art and one of the best-equipped in the world.Clarke 1999, p.157 Autosport Jun 27 1991Laban 2001, p.221Bernard et al. 2023, p.53 It now housed the race-control centre, media centre, corporate hospitality suites as well as a 2900-seat grandstand. At a practical level, there was accommodation for 46 pit spaces, each 15 x5 metres and five times the size of the previous pit-space. The pit-lane was 15m wide with a further 3m zone next to the pit-wall for the teams. The pit straight was also widened to 12 metres. It was inaugurated on the Friday night with celebration and fireworks.Clarke 1999, p.160 Autosport Jun 27 1991Laban 2001, p.222Bernard et al. 2023, p.83 Out on the track, the Indianapolis and Arnage corners were modified to provide greater run-off areas. The chicanes that were installed on the Hunaudières straight the previous year were resurfaced, smoothing out the bumps that had been so problematic. Finally, the signalling pits at the Mulsanne hairpin were demolished. Another structure dating from the 1956 renovation, they were now deemed redundant with the universal use of car-radios by the teams.Bernard et al. 2023, p.41
This year saw the advent of the Empreintes des Vainquers in Le Mans city. The project was the idea of Bernard Warain, akin to the Hollywood walk of fame, around the Place Saint-Nicholas. It started a tradition that, at the start of each racing week, the previous year's winners would leave their hand and footprints embedded in a plaque on the pavement for posterity.Bernard et al. 2023, p.307
Coach tours for the British fans to get to and from the race ranged from £60 to 70. Prices for the race included a £28 entry ticket, with £10 for a shuttle-bus around the circuit. Grandstand tickets included £25 for the new Pit Stand up to £38 for the Dunlop stand, with camping costs around the track going for around £13-20.Clarke 1999, p.156 Autocar Jun 12 1991
The ACO changed their mind from the previous year, dropping the extra half-hour of qualifying in the first sessions of both days, thus returning to 4hours total on Wednesday and Thursday. To further ensure the promotion of their new Sports Car regulations, FISA had decreed that the top-10 grid spots had to go to Category 1 cars in the SWC races, irrespective of their qualifying time, with the Group C cars arranged behind them.Spurring 2014, p.57
Entries The FISA entry-list debacle and the subsequent arrangements played havoc with the ACO and their race-organisation.
The accommodation with the WSC manufacturers did indeed stymie Nissan and Toyota's plan to compete, as neither were in the series and no-one else ran their engines. After the decision was released, deals were quickly made with the championship teams to enter supplemental cars on behalf of other teams, and in the end a reasonable total of 46 cars was received, matching the number of berths in the new pit complex.
This year, the Spice-Fords were joined by Peugeot, Jaguar and Mercedes-Benz in the 3.5-litre formula. Built primarily for the sprint-race formats, it was questionable what their endurance capabilities were. Jaguar and Mercedes-Benz had the luxury of also being able to call upon their older, Category 2 (Group C) cars. Porsche engines dominated that class, with 19 cars from Porsche and Cougar. Mazda was the sole Japanese representative, now also put into Category 2, and running the full Championship.
Jaguar had beaten Porsche in 1988, Sauber-Mercedes had defeated Jaguar and Porsche with a 1-2 finish in 1989. Then, with Mercedes boycotting the 1990 race, Jaguar had their own 1–2 victory. So the 1991 race was keenly anticipated as the final showdown between the dominant marques of Group C, Jaguar and Mercedes-Benz.
In the end, the starting grid of 38 cars was the smallest in almost 60 years.
Class Quantity Turbo+rotaryengines Category 1 14 / 10 0 / 0 Category 2 32 / 28 27 / 23 Total Entries 46 / 38 27 / 23 Note: The first number is the number accepted, the second the number who started.
Category 1
Defending champions, Jaguar had prepared a new model for the SWC. The XJR-14 was designed by Ross Brawn; it was fitted with the Jaguar-badged version of the Ford-Cosworth HB Formula 1 engine that could develop 650 bhp at over 11000rpm.Spurring 2014, p.63 It featured a two-tier rear wing and a bubble canopy, that effectively doubled as a door.Wimpffen 2008, p.370 Per the FISA regulations, SWC teams had to enter at least one of the 3.5-litre cars at Le Mans. Two cars were entered, though only one arrived, to be driven by Teo Fabi, Andy Wallace and Kenny Acheson. TWR also brought four XJR-12s in Category 2. The cars were all decked out in a lustrous new purple paintjob.
After missing the previous year's race, Sauber and Mercedes-Benz returned to Le Mans. Having won the World Championship for the past two years, they entered this year's Championship with the new Mercedes-Benz C291, with its purpose-built 3.5-litre Mercedes M291 flat-12 engine. It was also one of the first sports car to feature a sequential gearbox.Wimpffen 2008, p.369 A single car was entered and the Mercedes Junior Team of Karl Wendlinger, Michael Schumacher and Fritz Kreutzpointner were assigned to the car. As with Jaguar, this thereby allowed them to enter their Group C championship-winning C11 cars as well.Spurring 2012, pp.66-7