The Porsche 961 was a racing car built by Porsche and based on their 959 sports car. It was intended for Group B sports car racing, complementing the purpose-built 956 and 962C which ran Group C in the World Sports-Prototype Championship. The 961 project was short-lived, running only three races and seeing the construction of only one car. Plans to sell the car to customers were scrapped when the Group B class was canceled.
Development
In the early 1980s, the Fédération Internationale du Sport Automobile (FISA) reorganized their classification structure for motorsports. Two new categories, known as Group B and Group C, were designated for use in the World Sports-Prototype Championship. Porsche had developed the 956 for the Group C rules, and following the 956's debut, began work on developing a Group B car. An initial prototype concept, named the Porsche Gruppe B, debuted in 1983, after which plans were made to build the car for production and provide racing versions for customers as had been done with the 956.
By time the Gruppe B had been launched as the production 959 in 1985, Group B rules had been altered by FISA to better suit the class' use in the World Rally Championship rather than the Sports-Prototype Championship. Plans to develop multiple customer cars for sports car racing were therefore scrapped by Porsche, but development continued on the production of car which could be factory run in order to put the car's development to use. This lone racing car, built on 959 chassis No. 10016, became known as the 961.
The 961's engine was a Porsche Type-935 unit. This twin-turbocharged engine was not only used in the 959, but also in the Group C 956 and later the 962C. At the race in June, Metge was joined by fellow Frenchman Claude Ballot-Léna
thumb|left|200px|The Porsche 961 as it appeared for the [[1987 24 Hours of Le Mans]]
Later in 1986, the 961 was moved to the United States and entered in the Camel GT Championship's final round at Daytona International Speedway. The car was reclassified once again by International Motor Sports Association, this time being entered in the GTP category alongside sports prototypes like the 962. Drivers Kees Nierop of Canada and Günter Steckkönig of Germany were assigned to the car. The 961 however struggled with the banked turns of the Daytona circuit. The 961's Dunlop tyres were pushed beyond their limits and suffered several blowouts while the car was at full speed.
Porsche continued to develop the 961 into the 1987 season where it was prepared once more for Le Mans. The car was repainted in the colors of Rothmans to match the scheme used by the factory 962Cs. Swiss driver Claude Haldi was assigned to partner René Metge, but the two were later joined by Kees Nierop whose 962C had been destroyed in a qualifying accident. Although the 961 managed to run as high as 11th overall in the race, Kees Nierop crashed the car after a mis-shift. The car was stopped and retired after it caught fire as Nierop attempted to return to the pit lane.
Following the Le Mans difficulties, and with no championship with which to run the 961 against similar machinery, the project was canceled.