After the end of the race in 1986, which, in addition to a failure of the P86, ended with 12th place overall for 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 pool the limited resources in a new project.

Philippe Gache, Roger Dorchy, and Dominique Delestre agreed to drive a car capable of that top speed at Le Mans 1987.

The basis of the project and the key to the long-term cooperation between Welter and Peugeot was the PRV engine.

In the 1980s, many observers also saw a hidden Peugeot factory entry behind the World Championship racing cars.

Almost all WM prototypes had hidden rear wheel arches; in the case of the P87, particular attention was paid to this component.

In order to be able to use the ground effect optimally, the P87 had an extended wheelbase compared to its predecessor models.

The problem with the engine management was solved in the Welter workshop and the car was tested again on a new and not yet opened section of the motorway.

In practice, the team only managed 21st place on the grid, which came as no surprise as the car lost a lot of time in the corners.

In the race – Roger Dorchy drove the first stints – the turbochargers broke after 13 laps and the team had to give up.