The Mercedes-Benz C111 could have been Germany's most influential supercar, but this bizarre Wankel-engined machine never made it to production. Today marks 50 years since its unveiling at the 1969 Frankfurt Motor Show – here's our road test to celebrate the half-century.
Despite huge interest from potential buyers, the C111 was never put on sale, but it pioneered many technologies we now take for granted
“It’s insured for about $6 million, but that’s probably rather conservative,” says Matthias Chwal, the Mercedes-Benz minder who is accompanying this C111. Just 14 examples of Merc’s mid-engined technology demonstrator were built, and the one I’m about to drive is C111 II, revealed in 1970.
Its predecessor, the original C111, debuted just a few months earlier at the 1969 Frankfurt motor show, where it had eager visitors handing Mercedes staff blank cheques for the opportunity to buy one. Despite that, the C111 was kept entirely in-house, the pretty, glass-fibre bodied, gullwing doored wedges used as research and development vehicles, breaking a few speed and endurance records along the way.
None have ever been sold, which plays a big part in the C111’s mystique. When new it didn’t exactly fit with the company’s strong safety push. Add in the impending fuel crisis and the fact that early C111s used a Wankel rotary engine – not noted for their efficiency – and the decision not to proceed with a production version seems sensible.
Looking at it now, it’s difficult to believe that such a beautiful car was an experimental hack for new technologies, but this vehicle was used to test anti-lock braking and air-conditioning systems, while the windscreen's leading edge reveals the tell-tale sign of an early integrated radio antenna.
Mercedes-Benz’s engineers must have been the envy of their colleagues, trying to pick up a signal on the Becker Grand Prix radio while sitting in a car that was more than a visual match for mid-engined Seventies supercars such as the Lamborghini Miura and Ferrari 365 GT4 BB.
The flying buttresses, the scalloped intakes on its front and its flanks, plus those signature gullwing doors were overseen by Mercedes-Benz’s then Chief Stylist, Friedrich Geiger. Today, only the high profile tyres and the pop-up headlights betray the C111’s vintage.
Later iterations would see their styling changed to suit their role as speed and endurance record chasers, fitted with a variety of engines, including in-line turbodiesels and turbocharged V8 petrol units. The final car, C111 V, with its streamlined body and a twin-turbo 4.8-litre V8 engine with almost 500bhp, would achieve a quite incredible 250.9mph around Italy’s Nardo test track.
Sadly, the C111 II’s original Wankel engine is sitting somewhere on a shelf in Stuttgart, replaced by a V8 from the R107 350 SL. An output of about 200bhp is somewhat down on the 350bhp its original four-rotor engine produced, but that V8 is period correct, as the C111 II used the same engine later in its life as an experimental car.
Given its non-production status, the interior is remarkably well finished. The chequered seats are beautifully evocative of the Seventies, while the latticework wheel-rim is thin and nicely weighted. The rev-counter’s hastily painted red line is at 6,500rpm, though the numbers run up to 10,000rpm for that Wankel unit. There’s a note stuck on the dash that suggests a 120km/h maximum speed (just over 74mph) which, given the car's value, is not something I’ll be ignoring.
Turning the key and hearing that V8 fire up is an absolute joy. It’s a bit lumpy initially, but it soon settles to a nice even rumble. Meanwhile, the gearbox, a dogleg five-speed ZF manual, needs some practice, but it’s accurate enough when you get it right.
By modern standards, the C111 is brisk rather than fast, though back in 1970 it must have felt ridiculous with an additional 150bhp and four screaming rotors in the back. The ride is beautifully composed and the suspension features anti-dive geometry that would make it on to production Mercs, though the body lean around the tight, testing track at Mercedes-Benz World is sizeable.
On the up side, the C111 grips remarkably well and can be driven hard – at least, as hard as a near-priceless 45-year-old car should be.
On the road, visibility proves to be excellent, as the C111 slips through traffic on a Friday afternoon in Weybridge for the first – and almost certainly – last time. Unsurprisingly, it turns some heads.
Driving it is a real privilege, one that a blank cheque couldn’t buy. That it didn’t ever make production is a real shame, as it’s a remarkable car. There were no doubt some exhalations of relief in Italy when Mercedes chose not to sell it, and rightly so, as the C111 could have changed the supercar story as we now know it. However, its place in history is no less significant, especially if you value a chilled interior, good brakes and a crisp radio signal.
Thanks to the Brooklands Museum for allowing us to shoot the C111 on the famous banking of the Brooklands track:Brooklandsmuseum.com
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