The Porsche WSC-95 (sometimes referred to as the TWR WSC-95) was a Le Mans Prototype originally built by Tom Walkinshaw Racing. It was modified by Porsche from the original Group C Jaguar XJR-14 from which it derived, and run by Joest Racing. Originally intended to race in the IMSA World Sportscar Championship, the WSC-95 saw very little race action even though it won the 24 Hours of Le Mans in both and without being acknowledged as a factory supported project. It was later upgraded to the Porsche LMP1-98 before being retired. Only two cars were ever built.
Development
In 1994, Porsche approved the beginning of a project to develop a prototype for the International Motor Sports Association (IMSA) series, running under the World Sports Car (WSC) regulations. The car was not a factory-backed effort, yet was approved by Porsche and use some of their expertise and most of all their powerplant. Tom Walkinshaw Racing (TWR) used the XJR-14 chassis number 691, modified by Porsche.
For an engine, Porsche used one of their longest running motors, the Type-935 turbocharged Flat-6. Originally used in the Porsche 956 in the 1980s, the engine was still powerful enough to power modern prototypes. While Porsche's new 911 GT1s used a 3.2 Litre engine, the WSC-95 used a smaller 3.0 Litre engine. Although smaller, this gave the WSC-95 a better fuel economy than the 911 GT1, which was useful over long race distances.
Unfortunately, the IMSA WSC regulations were changed prior to the 1995 season, leading to Porsche canceling the project. However, in February 1996 Reinhold Joest of the Joest Racing team convinced Porsche to give the unused prototype to his team, and for them to compete in the 24 Hours of Le Mans. With approval from Porsche, Joest put forth the money to allow for the construction of a second car from scratch, as well as the slight modifications to the existing car in order to meet the Le Mans Prototype (LMP1) regulations. Porsche agreed to help in the development of the car only if Joest agreed to pay for the services.
Following the success of the WSC-95s in winning both the and 1997 24 Hours of Le Mans, Porsche decided to take over the project themselves. Both WSC-95 chassis underwent major revisions to their bodywork. The nose was raised in the middle, while to the sides sculpting allowed for the moving of the air intakes for the engine, necessitating the removal of the large scoop underneath the rollbar. The sides of the car were also redesigned, with the large opening for the radiator vents covered up while exhaust vents were also rearranged. The Type-935 Flat-6 was also upgraded, expanded out to 3.2 Litres. Having become a proper factory undertaking, the cars became officially known as the Porsche LMP1-98s.
Racing history
The two WSC-95s were completed just in time for Joest Racing to go to the Le Mans test session in May. There, the two cars showed their pace early by setting the fifth and tenth fastest times, easily beating the factory Porsche 911 GT1s. A few weeks later at Le Mans, the WSC-95s showed their improvements and the #8 entry was at the pole position, while #7 was seventh. However the 911 GT1s had also improved, taking the fourth and fifth fastest qualifying positions. During the race, the #7 WSC-95 led for nearly the entire race, although closely followed by the factory 911 GT1s. The #8 entry remained towards the front as well, although it succumbed to mechanical failures caused by a collision on the track during the closing hours. In the end, the #7 entry of Davy Jones, Alexander Wurz, and Manuel Reuter took the overall victory, a mere lap ahead of the following Porsche 911 GT1. The car experienced lighter tyre wear than competitors in the GT1 class and was able to make up time by only changing tyres at every third pit stop made for petrol.