In preparation for the launch of the 911 Turbo road car and the subsequent 934 and 935 competition cars, Porsche fielded the 911 Carrera RSR Turbo 2.1 during the 1974 season. As the road car was not yet built in sufficient numbers, it was not homologated and raced in the prototype class instead. This was of little concern to Porsche, who were more interested in testing and developing car in a proper racing environment and also welcomed any publicity this would generate for the production model. Despite racing against purpose-built competition cars like the Matra 670 and Alfa Romeo 33, the 911 Carrera RSR Turbo did score some great results, most notably a second place finish at Le Mans. Over the years, we caught up with three of the fours cars built, including the example that finished second at Le Mans, while a sister car is seen in action at the recent Le Mans Classic. The result is this 36-shot gallery, which illustrates our detailed article.
Another rare experimental Porsche is the 917 PA 16 Spyder, which is one of two PA Spyders built. Never raced, it was tested during the 1971 season with a massive 16-cylinder engine with an eye on competing in the Can-Am championship. The complicated and heavy engine was ultimately abandoned in favour of a turbo-charged version of the flat 12 engine. The ultimate development of this engine produced in excess of 1,100 bph and was found in the 917/30. At the Goodwood Festival of Speed, we captured the chassis offered by RM Auctions earlier this years and have used the opportunity to expand our gallery of this mighty machine to 65 shots.

Enjoy the links:

1974 Porsche 911 Carrera RSR Turbo 2.1 - Images, Specifications and Information

1973 Porsche 917/30 - Images, Specifications and Information

1971 Porsche 917 PA 16 Spyder - Images, Specifications and Information