Technical analysis of the Porsche-Kremer CK5 Group C car

During the early 1980s, Kremer Racing sought to compete in the Group C category by developing a bespoke vehicle rather than converting existing chassis. Partnering with Ekkehard Zimmermann of DP Motorsport, the Cologne-based team engineered the CK5, a closed-cockpit sports car built on a tube frame that combined design elements from the Porsche 908/3 and 936.

The vehicle departed from the industry trend of utilizing ground effect aerodynamics. Due to the placement of the engine and transmission, which were kept low for weight distribution, the integration of a diffuser was not feasible. Despite this, the CK5 utilized a 2.8-liter twin-turbocharged engine capable of producing between 630 and 720 horsepower, exceeding the output of contemporary factory machines.

A notable feature of the CK5 was the dorsal fin mounted on the engine cover. While initially conceived by Zimmermann to prevent the wide rear wing from bending under stress, it provided significant aerodynamic benefits on high-speed sections. Drivers noted improved straight-line stability, which became a signature characteristic of the vehicle's handling.

Two examples of the CK5 were constructed and campaigned from 1982 through 1985. The project remains a notable case study in motorsport history, reflecting an era where mechanical solutions were derived from hands-on testing rather than modern wind tunnel optimization.