Rule changes for the 1966 24-Hours of LeMans introduced the Group 4 Sports Car class for which 50 examples had to be built rather than the GT class requirement of 500 examples. The new rules fit Porsche's interest in endurance racing perfectly. The Porsche 906 Carrera 6 type introduced that year, utilizing the Type 911 2-liter flat-6 engine, 5-speed transaxle. Long the dominant marque in 2-liter racing, the new Carrera 6 continued the supremacy with a significant step-up. Weighing under 1,400 pounds with just 220 horsepower, this new tube frame Porsche proved a challenger to win Le Mans overall for the first time. Six 906/6 entries were on the starting grid for the 24-Hours in 1966, three as Sports Cars and three as Prototypes due to some long tail specifications in the latter.
Chassis number 906-155 was the 58th of 65 produced. It was the #33 car driven by Petre Gregg and Sten Axelsson.
In 1967, the car went to Gerhard Koch. He used it as a prototype in the 1967 world endurance. Later, the car in a Spyder conversion was acquired by Karl Adolf Kneip.
He raced the car in the 1975 ( 3 races) and 1976 (4 races) interserie championship.( He then bought a KMW SP 30 car).
