WM P87
The WM P87 was a Group C sports car developed by Welter Racing in 1987 and used in sports car races until 1988.
Background and project 400
In 1976 Gérard Welter and Michel Meunier founded a racing team in order to regularly compete in the Le Mans 24-hour race with sports cars . The small racing team developed amazingly fast racing cars, which, however, often lacked stability. Target arrivals at the 24-hour race in western France remained the exception. After the end of the 1986 race , which, in addition to the failure of the P86, ended in 12th place overall in the P83B , driven by Claude Haldi , Roger Dorchy and Pascal Pessiot (67 laps behind the winners Hans-Joachim Stuck , Derek Bell and Al Holbert in the factory - Porsche 962C ), Welter decided to bundle the limited resources in a new project.
The goal was now to surpass the 400 km / h hurdle at top speed at the fastest point on the circuit in the race in one of the next two years. A lot of preparatory work had to be done for this. First of all, Welter had to convince those responsible at the ACO of the company's purpose and feasibility. The main aim was to get the ACO to take official measurements so that any record would be recognized. Then a tire manufacturer had to be found who could supply the necessary products. The French tire manufacturer Michelin supplied tires with a special compound and guaranteed a speed of 410 km / h.
The drivers also had to be involved in advance, because such high speeds were and are the exception even in professional motorsport. Philippe Gache , Roger Dorchy and Dominique Delestre agreed to drive a vehicle that could reach this top speed in Le Mans 1987 .
Development and technology
The PRV engine was the basis of the project and the key to the long-term cooperation between Welter and Peugeot . In the 1980s, many observers saw behind the world championship racing car a hidden Peugeot factory outing. As a Peugeot designer, Welter had excellent contacts with the Peugeot board, but the Welter team was never a works team. The PRV engine was a cooperation between Peugeot, Renault and Volvo and was intended for series production. Derivatives from this found their way into motorsport. In 1987 Welter was able to fall back on the most powerful example of this type of engine to date. The 2.8-liter V6 engine had two turbochargers and developed 890 hp.
Welter was allowed to use the Peugeot wind tunnel in Sochaux every Sunday for five months . Almost all of the World Cup prototypes had concealed rear wheel arches; In the P87, particular attention was paid to this component. The Welter aerodynamicists wanted to avoid even the smallest wind turbulence on the side flanks. The team also found a special solution for supplying air to the charge air coolers. The air was sucked in from under the car through special pipes under the suspension. In order to be able to optimally use the ground effect , the P87 had an extended wheelbase compared to its predecessor models. The first attempts without a rear wing were abandoned because the car was almost unbalanced in the corners.
Races
At the Le Mans test days in May 1987, the team hardly got to drive. Roger Dorchy barely managed two laps in a row because there were constant problems with the engine management. The fastest measured speed on the Ligne Droite des Hunaudières was 356 km / h. A high speed, but not a record. The problem with the engine management was fixed in the Welter workshop and the car was tested again on a new and not yet opened section of the motorway. The measurement carried out by Welter showed 416 km / h: Roger Dorchy again at the wheel. Whether Welter's measurement was really precise remains open to this day.
The Le Mans race was short. In practice, the team only finished 21st on the grid, which was no surprise, as the car lost a lot of time in the corners. In the race - Roger Dorchy drove the first stints - the turbocharger failed after 13 laps and the team had to give up. The ACO gave the top speed of 387 km / h.
In 1988 Welter returned to Le Mans. The P88 differed from the P87 in that it had an even more powerful engine. Roger Dorchy officially broke the 400 km / h sound barrier with 405 km / h. The P87 was also used again. Pascal Pessiot and Jean-Daniel Raulet stopped a defective gearbox after driving 22 laps.
Web links
Individual evidence
- ↑ In the covers of the rear wheel arches are barely edges to discover ( Memento of the original March 4, 2016 Internet Archive ) Info: The archive link is automatically inserted and not yet tested. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ The P87 in the early stages of the race
