The power of the new Porsche 917 was shown by Stommelen on the first night of practice when he put in a blistering lap of 3:22.9 to take pole position. This was over 2 seconds faster than the sister car of Vic Elford. It was also 0.7 seconds faster than the lap record held by the big Mark IVs of Denny Hulme and Mario Andretti in 1967 (set without the Ford chicane present). Despite a top speed over 20 km/h slower than the Fords, this was achieved with the great advances in downforce. In the end, Porsche chose to only race two of their three 917s. Woolfe had busted his engine in practise grabbing 1st instead of 3rd but was able to get a replacement one from Porsche.