Joest Racing
During his three decades of sports car racing, almost exclusively in Porsches, he won the 24 Hours of Daytona four times (1983, 1985, 1989, 1991) and the DRM in 1982 and 1983, with the Porsche 936 and Porsche 956 entered by the Joest Racing team. In the mid-1970s, he raced a Porsche 935K2 improved and entered by the Kremer Racing team from Cologne.