Mercedes C111 Wankel Research Vehicules 1969 - 1970
The Mercedes C111 research vehicule introduced in 1969 was not just interesting as a concept sports car illustrating a possible successor to the gull wing doors 300 SL but especially because it was powered by a Wankel rotary piston engine than by a reciprocating piston engine. At the time, many manufacturers were interested in Felix Wankel's unconventional propulsion system. Mercedes Benz too had been experimenting with Wankel engines since 1962. However, the Wankel engine was to be extensively road tested before being fitted in production cars. The last Mercedes with a rotary piston engine from this serie was the four rotor DB M950 KE409 of the C111 II in 1970 (photos 1 and 2).
The performances of the C111 (photos 5, 6 , 7, 8, 9) even with the three rotor engine was convincing right from the start. In 1969, the Wankel engine developed 280 hp from 600 cubic centimeters of chamber volume per rotary piston and gave the car a top speed of 260 kph; with this engine the car accelerated from standstill to 100 kph in five seconds. The C111 II of 1970 was powered by a large four rotor Wankel engine which developed 350 hp and gave the car a top speed of 300 kph. The second C111 (photos 1 and 2) accelerated from standstill to 100 kph in 4,8 seconds.
The development department of Mercedes Benz eventually succeeded in solving the engineering design problems involved in rotary piston engines, especially in engine mechanics, but the problem of the Wankel engine's poor degree of efficiency, due to the elongated, variable combustion chambers of the rotary piston engines principle, was not to be overcome with technical modifications.
The engines of the C111 versions showed excessive fuel consumption compared to equivalent reciprocating piston engines and the level of pollutants in the exhaust gas was too high, so that Mercedes Benz discontinued work on this type of engine in 1971. Today, from all the manufacturers involved at the time in Wankel engine development, Mazda is the only one still working on it and proposing a production model equipped with this type of engine.
The C111 Research vehicules program was converted in 1976 to Diesel engine
MERCEDES C111 Wankel Research Vehicules 1969 - 1970 Wallpapers 1280x1024