At the Frankfurt International Motor Show in late 1969, Mercedes-Benz announced a car that didn't fit in with the rest of their products, it was called C 111. It caused quite a stir and people were queuing in great numbers to lay eyes on what the press dubbed a “test lab on wheels”

The result of this was a wedgy body shape with sharp lines and gullwing doors. To further attract attention, it was painted in an orange metallic that would prove to be an iconic match for this shape.

The main reason the C111 was what lay under the hood. A rotary Wankel engine would power one of the best early examples of a rotary-powered performance car.

The C111 was the supercar icon of the 1970s and as the years passed it became an instrumental research tool for Mercedez Benz.

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A Legend In The Making

c111 mercedes front end
via Mercedes-Benz

Originally, the C 111-I was only built in order to test the Wankel engine. The first of which happened to be a three-rotor, developing 280bhp that could provide the power to see a top speed of 162 mph which was remarkable for the time.

Then a couple of months later a heavily revised version of the C 111 was presented at the Geneva Motor Show. This time called the C111-II, it featured a four-rotor Wankel engine with a max output of 350bhp. The car did 0-62 mph in 4.8 seconds and went on to reach an even crazier top speed of 186 mph, an outrageous number for the 1970s.

Designed by Bruno Sacco, a legendary Italian car designer, his sketches would come to life using fiberglass body panels and gullwing doors. This came as Mercedes wanted to test the limits of this material in car production. this car also trialed new multi-link rear suspension technology.

c111 4 rotor jay leno
Via YouTube

Back in the late '60s and early 70's the Wankel rotary engine was the only new engine technology that had been introduced in the entire 20th century. The efficiency of this new tech meant that it was beginning to find its way into many production cars.

Mercedes ran with the idea that they could show the public what was able to be done with what seemed to be the engine of the future.

The Wankel was not free of problems, however. Fuel consumption wasn't great, which with the 70's oil crisis was not ideal for consumers and along with this seals tended to wear much easier, and not many mechanics knew how to fix them yet.

As we know from history reliability is at the heart of the Mercedes-Benz brand and unfortunately, the rotary Wankel just didn't cut it. The C111-II never went into production, but it did serve as an amazing prototype that would go on to inspire Mercedes in future projects.

Of these first two Wankel engined iterations of the C111, only 13 of them were made. Making these some of the rarest cars ever.

Research And Development

c111 interior 1970
via Opera News

The 4 and 3 rotor Wankel engine was left behind and the focus turned to diesel technology  Record-breaking versions of the C 111 once more caught the attention of the public: the C 111 did several runs on the high-speed testing track in Nardo, Italy, these times would produce many world records over a variety of distances.

On the very first run, the newly updated C 111-II D, almost identical on the outside in comparison with 1970, was powered by a revised five-cylinder diesel motor that would churn out 190bhp.

In 1978, the C 111-III developed an output of 230 hp with the help of an extra intercooler. However, the new record-breaking car had very little in common with the original C111. The new silver-painted body sat on a floor unit with improved dimensions that were even more streamlined.

C 111-IV record lap nardo
via Mercedes-Benz Museum

The final call was the record-breaking C 111-IV which came through in '79 with a whole bunch of new aerodynamic updates, big spoilers, a new front end, and 2 fins at the rear. Powered by a regular production 4.8-liter V8 engine that was tuned up to generate an incredible 500 bhp.

This iteration of the C 111-IV was not just a research car but a model that went on to achieve award-winning performance.

The C111 was never intended as a race car or even a production car. It was simply a guinea pig for all of Mercedes's wild and innovative ideas at the time. The result was magnificent and even after pressure from prospective buyers and critics, Mercedes still didn't move forward with production.

Instead, they took all that they had learned from the C111 and pushed it into new models that would evolve the brand and push their technology forward. The C111 will forever remain one of the best cars that never made it.

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