1970 Porsche 917 KH

The Porsche 917 is surely the most famous Porsche racing car, although at the beginning of its career it had the dubious reputation of actually being undriveable. The reason for the teething troubles was quite simply a time problem: with just nine months between the first drafts and presentation at the Geneva Motor Show on 13 March 1969 there was no time left for testing. The air-cooled twelve-cylinder vehicle drove straight from the drawing board to the racetrack, so to speak.

The design process had focused on aerodynamics – at the expense of downforce, i.e. driving stability. But one thing after another: in 1968 the FIA changed the regulations for the World Sportscar Championship out of the blue and the displacement limit was raised from three to five litres. This meant that the three-litre Porsche 908 was only competitive to a limited extent. A new five-litre car was needed.

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