Mercedes revealed the C 111 concept car at the 1969 Frankfurt motor show, backing its slippery, Bruno Sacco-penned lines with sizzling orange paint (officially, rosé wine), glass-fibre bodywork, roof-hinged gullwing doors and a 280-horsepower three-rotor Wankel engine.
Rotary Wankel engines were then thought to be the power plants of the future, and Mercedes wanted a suitably exotic test platform to study this new engine. That car was quickly followed by the C 111-II at the Geneva show of 1970, an updated version propelled by an even more extreme, 350hp four-rotor Wankel that could fire the C 111-II to 100km/h (62mph)in 4.8 seconds and on to a top speed of 300km/h.
While the C 111’s lines were a dramatic rebuttal to the outgoing era of over-stylised concepts and customs, its eye-catching orange paint was customary for Mercedes test cars of the time.
But times change, and the fuel-price shocks of the’70s resulted in the C 111 being revised with a modified version of a fuel-sipping five-cylinder turbodiesel engine intended for Mercedes’ sedate sedans. The C 111-IID featured a 3-litre diesel unit producing 190hp.
The C 111-III saw the orange test paint replaced by the traditional hue of the Mercedes Silver Arrow race cars, as the intercooled 230hp turbodiesel car took to the track at Nardo, Italy, to set world speed records.
The final iteration, the C 111 IV, ushered in the model’s most radical performance era. A true supercar, the IV was equipped with twin vertical stabilizers and a 500hp 4.8-litre gasoline V8, good enough to help the car set a closed-circuit speed record of 403.978 km/h in 1979, a decade after the first C 111’s debut.
And now, the C 111 family has been recalled from the bowels of Mercedes’ storage centre, dusted off and brought out for the public’s enjoyment.
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