Stommelen won the pole position for the 1969 24 Hours of Le Mans in a Porsche 917 a year after finishing third in a Porsche 908. In this year, he became the first man to reach speeds exceeding on the Le Mans circuit's Mulsanne Straight in his Porsche 917 LH. In 1970, he made his Formula One debut with Brabham with sponsorship obtained from the German magazine "Auto, Motor und Sport" and raced both sportscars (Toj and Porsche works teams) and Formula 1 throughout the 1970s.