The “shark fins” on the tail gave the Porsche 917 KH 1971 greater directional stability and reduced wind resistance by 11 percent. In 1971 a veritable armada of six Porsche 917s started at Le Mans. The car with start number 22 was special. The white race car with the characteristic Martini stripes had the new “shark fins” on the tail that Porsche had first used in pretraining in April. This 917 was also the first Porsche with a magnesium tubular frame to be used in a race.