In the 1960s and 1970s Mercedes was experimenting with new engine technologies, and used the C111 as common platform for the tests.
Other experimental features included multi-link rear suspension, gull-wing doors and a luxurious interior with leather trim and air conditioning.
The first version of the C111 was completed in 1969. The car used a fiberglass body shell and with a mid-mounted three-rotor direct fuel injected Wankel engine (code named M950F).
Frankfurt, September 1969: expectations were already running high. Rumours had been circulating for quite some time that Mercedes-Benz was planning to launch a sensation at the International Motor Show (IAA) in Frankfurt. But the car finally unveiled by the Stuttgart manufacturer surpassed even the wildest expectations. What the journalists got to see was a super sports car with gullwing doors and a Wankel rotary engine. It was a research vehicle that quickly became the absolute dream car of the 1970s.
ENGENEERING AND DESIGN:
The concept as a whole made the C 111 the absolute dream car of the seventies. Its engineering lived up to the promise of Bruno Sacco’s futuristic styling. Both the C111-I of 1969 with its three-rotor Wankel engine (206 kW/280 hp) and the C 111-II of 1970 with four-rotor Wankel engine (257 kW/350 hp) impressed with their effortlessly superior driving performance, delivering top speeds of 270 and 300 km/h respectively, while the C 111-II could accelerate from a standing start to 100 km/h in 4.8 seconds. Yet even when the Mercedes-Benz engineers pushed the Wankel engine to the very limits of its design, the result did not meet the high standards of Mercedes-Benz in terms of reliability and durability. The more stringent emissions legislation in the United States was to prove an added complication.
SERIES PRODUCTION REMAINED A DREAM:
But it was not only the disadvantages of the rotary piston engine that ultimately led to the decision not to proceed further with series production of the C 111. By the early 1970s, passive safety was becoming a more and more important factor in automotive development. The plastic bodyshell of the C 111 had an inherent disadvantage in this respect, compared with a conventional sheet steel body. And so it was that, in 1971, Mercedes-Benz made the decision not to move forward with series production of the sports car. The dismay among automobile enthusiasts was considerable. More than one such fan had taken a punt and submitted an order to the plant at Untertürkheim, along with a blank cheque – all to no avail.