There are at least eleven variants of the 917. The original version from 1969 had a removable long tail/medium tail with active rear wing flaps, but had considerable handling problems at high speed because of significant rear lift. The handling problems were investigated at a joint test by the factory engineers and their new race team partners John Wyer Engineering. After exhaustive experimentation by both groups, a shorter, more upswept tail was found to give the car more aerodynamic stability at speed. The changes were quickly adopted into the 917K for Kurzheck, or "short-tail".

 

But even after the birth of the «K» the 917 was modified from the different teams in a huge amount of different ways.

 

For those of you that have investigated the different original cars you may have noticed the most visual parts like;

-Two different front corners.

-Three different front lids

-Five different rear sections

-With and without roof window

 

But what many do not know is that there are both a narrow and wide version of the front of the car.

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The 917CFK is based on a narrow front and a wide rear 1970 John Wyer (Gulf) rear section.