The Mercedes C111

Three generations of the Mercedes-Benz research car C 111: C 111-II, 1970 (in the middle), C 111-I, 1969 (on the left), the first prototyper version of the C 111-I (on the right).

Mercedes-Benz C 111 experimental vehicle with V8 engine (1970)

Mercedes-Benz presented the C 111 at the International Frankfurt Motor Show IAA in September 1969. With its extreme wedge shape and gullwing doors, the research vehicle had a glass-fibre-reinforced plastic body and was powered by a three-rotor Wankel engine with an output of 206 kW (280 hp). This futuristic sports car could reach a speed of up to 270 km/h. The following year, a revised version of the C 111 was shown at Geneva – but now with a four-rotor Wankel engine delivering 257 kW (350 hp). This version of the C 111 could accelerate from 0 to 100 km/h in 4.9 seconds and reach a top speed of 300 km/h. It was this second version of the research vehicle that served as the basis for a V8 variant of the C 111 containing the M 116 series engine (147 kW/200 hp), which Mercedes-Benz engineers and technicians used for the purposes of comparison with the rotary-engined sports car. Despite numerous orders, the C 111 remained an experimental vehicle and never entered series production. Mercedes-Benz instead went on to develop a series of record-breaking vehicles based upon it: the C 111-II D (1976) and the C 111-III (1977-1978, both with a five-cylinder diesel engine) and the C 111-IV (1979, V8 petrol engine with turbocharging).

Technical data – Mercedes-Benz C 111 with V8 engineProduction period: 1970
Cylinders: V8
Displacement: 3,499 cc
Output: 147 kW (200 hp)

In contrast to the other C 111 vehicles that Mercedes-Benz constructed with the rotary engine invented by Felix Wankel (six with a three-rotor engine in 1969 and six with a four-rotor engine in 1970), this C 111 has a rear-mounted reciprocating engine. When building the prototype in 1970, Mercedes-Benz engineers in Sindelfingen implanted a 3.5-litre, V8 production engine into a second-generation C 111 chassis to enable direct comparisons to be made with the four-rotor Wankel engine. This V8 engine was first used in 1969 in the luxury Mercedes-Benz 300 SEL 3.5 (W 109) and 280 SE 3.5 Coupé and Cabriolet (W 111) models, and also delivered a sporty driving experience in the 350 SL (R 107) launched in 1971.