Driving the C111 – the 1970s supercar that Mercedes never released
The 50-year-old supercar that Mercedes-Benz never sold was a radical, record-breaking wedge of ‘70s experimentalism.
Kyle Fortune is a freelance motoring journalist who has written for a host of newspapers, magazines and websites including Motor1.com, Car Magazine and the Daily Telegraph.
The Geneva Motor Show, 1970. Mercedes-Benz’s staff were having blank cheques thrust at them. Why? Because of a new supercar that the company had just unveiled. The C111-II was a radical wedge, as far removed from Merc’s usual conservative saloons as you could imagine. Mercedes had a car on its stand to rival its Ferrari 365 GTB 4 and Lamborghini Miura for beauty as well as performance.
Gullwing doored and built from glassfibre over a steel sheet frame, the C111 wasn’t just radical to look at. It was powered by a direct injection four-rotor Wankel M 950 F rotary engine with 350hp, which was said to be good for 186mph (300kph).
That very C111-II show car is today parked out front of the Mercedes-Benz Experience Centre at Brooklands, UK. And we’ve got the keys. Well, actually Matthias Chwal, the Mercedes-Benz Classic department’s minder who is accompanying it, has the keys, and as he hands them over says: “It’s insured for about $6m, but that’s probably rather conservative.” He’s not wrong, you could probably add a 1 in front of that 6, if not a 2.
Mercedes-Benz would build 16 C111s, but none were ever sold to customers, despite the plentiful blank cheques. They were built for internal use, the programme becoming the ultimate tease as they were pressed into service as research and development vehicles, testing new technology and breaking a few speed and endurance records in the process.
The oil crisis of the early 1970s quickly killed off the fuel inefficient Wankel rotary engines, and this C111 is fitted with a contemporary 200hp 3.5-litre V8 from a R107 350 SL. The original four rotor Wankel is sitting somewhere in Mercedes-Benz’s museum vaults. Later C111s would be powered by everything from inline turbodiesels to turbocharged V8s – a streamliner-bodied, twin-turbo 500hp 4.8-litre V8 managing 250.9mph around Italy’s Nardo test track in 1979.
Sitting in the Geneva car from 50 years ago, it’s difficult to comprehend that something so achingly pretty was used as a development hack. The interior is beautifully finished, with gloriously ‘70s chequer seats and a dashboard that looks production ready. There’s even a Becker Grand Prix radio mounted vertically in the centre console, which the test drivers used to test the C111’s early windscreen-integrated radio antenna. This car was also used to test ABS systems, as well as air conditioning systems. The latter is not working today.
There’s a bit of heat soak into the cabin through the bulkhead, but it’s not too uncomfortable. One period test saw Mercedes-Benz engineers place packs of butter in the boot to test how well insulated it was from the heat of the engine. Behind me that 3.5-litre V8’s burbling with intent, though Chwal’s asked respectfully that it’s not run over 130kph (75mph) and that there’s “no drifting”. Mindful of its value, that’s a given, but with Mercedes-Benz World’s test track at our disposal for a while, and then a run around some public roads, this once-in-a-lifetime drive can at least give me some meaningful impressions.
The driving position is classic supercar, but the view out is far greater than I’d anticipated, with good all-round vision. There are flying buttresses at the rear that afford some over the shoulder vision, while the slim pillars and large glazed areas make it less worrying in the traffic around Brooklands than I’d imagined. It’s a five-speed manual, a dogleg ‘box with first requiring a button push on the alloy lever before it engages, and the shift across its gate needs a bit of practice to manage smoothly and swiftly. The steering is light and precise, the brakes strong – hardly surprising given the relative lack of mass they’re dealing with – and that 3.5-litre V8 gives brisk rather than genuinely startling performance.
It's all a bit surreal, as while it all looks and feels like a production car, the fact it’s one of 16, and effectively priceless, does somewhat play on my mind as I’m driving it. I’m still enjoying it though, as after all, I doubt I’ll ever get the chance again. Around the track it reveals masses of body lean through the bends, but there’s real balance and poise, while that softness, and the huge sidewalls of the tyres, affords it a really comfortable ride later while out on the road.
Out there it’s got the capacity to stop traffic, which is hardly surprising. Its pretty lines still looking sensational today and they’re accentuated by contrasting matt black and ‘Weissherbst’ orange metallic paintwork, chosen by Mercedes-Benz to make it as visible as possible for safety reasons. It’s little wonder it caused such a stir back in 1970, and it’s difficult to imagine how different the supercar world might have looked had Mercedes-Benz productionised it and cashed some of those cheques.
But the company’s pragmatism won out. Nevertheless, the C111’s impact on more earnest production Benzes would be felt for decades. This 70’s supercar earned its keep as a developmental workhorse rather than a trinket for the world’s wealthiest car buyers. No doubt much to the huge relief of a few Italian firms…