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Porsche 917 Spyder
Premiere: August 17, 1969 Can-Am Mid-Ohio race
Interserie winner 1971
917 Spyder was the topless version of the 917 K, created for the Can-Am racing. There were two 917 Spyders created by the factory, chassis 917-027 and -028. The 027 was a test car and the 028 was made for action. As it was created for Porsche+Audi (PA), the American brand that marketed Porsches and Audis in the USA, the car was called the 917 PA. Only chassis 028 was called the 917 PA. It was raced by Jo Siffert at five Can-Am races in 1969. His best result was third at the Bridgehampton race. For the final round of the 1969 Can-Am, the car received a new showel-like nose. In this configuration it was only raced once.
The Can-Am setup gave the 4.5-litre more power (approx. 428 kW compared to the 382 kW in the "European" 917 in 1969). 917 PA was the first 917 with open rear end, something that would be transferred to the 917 K for the next season.
In 1970, the 917-028 stayed in the garage and in 1971 it was raced again, now with the 5-litre engine. Three racing teams in Europe built their own 917 spyders for the 1971 Interserie. These cars were built from the previously crashed 917 coupé chassis. 917-026 was the first Spyder to enter racing in Europe, then 917-007 and then 01-021 (not a Porsche chassis number). The 01-021 was created using some parts of 917-021 and remains of chassis 917-015. 4.5-, 4.9- and 5.0-litre engines were used.
In the Can-Am, the 917-028 (originally the PA) received a new shorter nose and rear fins during the season. The rear fins had appeared in the beginning of 1971 on all factory team 908/03 and 917 K racing cars and some private teams also upgraded their cars with that new feature.
The 1971 Interserie was won by 917 Spyder driven by Leo Kinnunen of A.A.W. Racing Team (he would also win the series in 1972 and 1973).
For 1972 Intreserie one more 917 Spyder was created from chassis 917-031. It was the chassis of the 1970 Zeltweg 1000 km winning and the 1971 Le Mans 2nd place 917 K coupé. The 01-021 chassis car gets a 5.4-litre engine, the first of this size among the 917s. The 917-028 (originally the PA), gets a 4.5-litre turbo engine by the end of October for the last Can-Am race of the 1972 season.
For 1973, the 917-028 (ex PA), got a body of the 917/10. Different engines were used, both normally aspirated and turbocharged, the most extreme of them the 5.4F12 twin-turbo.
The 16-cylinder prototype
The 917-027 factory spyder chassis was used only for tests and in 1971 even fitted with experimental 16-cylinder flat engines - 6.0-litre (566 kW) and 7.2-litre (647 kW). The 16-cylinder newer saw racing, because the turbocharged 12-cylinder would be cheaper and would produce more power. The engine tests on the 917-027 were made with the 917/10 in mind.
Article © James Herne / Stuttcars.com
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