The 905 began its first full season in Sportscar racing by participating in the 1991 championship.
Although the car was now quicker than the 1990 version, and indeed the heavily penalised Group C cars that were allowed to race, in the early part of the season the 905 suffered some performance and reliability problems but, more crucially for Peugeot, the car was a lot slower than the standard-setting Jaguar XJR-14 - a car that was able to match the lap times of most contemporary F1 cars (but not those of top cars such the Williams-Renault and McLaren-Honda cars that were at least 2 to 3 seconds faster per lap).

The car was however able to obtain a lucky win at the Suzuka Circuit.
Unfortunately, at the 1991 24 Hours of Le Mans, both cars entered did not last past the four hour mark.

To counter Jaguar in the remaining races of the championship the 905 was heavily revised, primarily in aerodynamics.
Carrying over only the cockpit of the previous car, the evolutionary 905B was created.
With the more notable changes consisting of a two-tier rear wing and an optional full-width front wing, including a more powerful SA35-A2 engine, the 905B made its race debut at the Nürburgring round of the 1991 series.
These advancements allowed the team to finish the year winning at Magny-Cours and Mexico with back-to-back 1-2 wins, thus completing the season in second place overall in the 1991 World Sportscar Championship season.
The 905 began its first full season in Sportscar racing by participating in the 1991 championship. Although the car was now quicker than the 1990 version, and indeed the heavily penalised Group C cars that were allowed to race, in the early part of the season the 905 suffered some performance and reliability problems but, more crucially for Peugeot, the car was a lot slower than the standard-setting Jaguar XJR-14 - a car that was able to match the lap times of most contemporary F1 cars (but not those of top cars such the Williams-Renault and McLaren-Honda cars that were at least 2 to 3 seconds faster per lap).
The car was however able to obtain a lucky win at the Suzuka Circuit. Unfortunately, at the 1991 24 Hours of Le Mans, both cars entered did not last past the four hour mark.
To counter Jaguar in the remaining races of the championship the 905 was heavily revised, primarily in aerodynamics. Carrying over only the cockpit of the previous car, the evolutionary 905B was created. With the more notable changes consisting of a two-tier rear wing and an optional full-width front wing, including a more powerful SA35-A2 engine, the 905B made its race debut at the Nürburgring round of the 1991 series. These advancements allowed the team to finish the year winning at Magny-Cours and Mexico with back-to-back 1-2 wins, thus completing the season in second place overall in the 1991 World Sportscar Championship season.
Peugeot 905