BMW launched the M1 in autumn 1978 at the 64th Paris Motor Show. Sports car fans and lovers were able to admire a super-low, extremely dynamic new model making it quite clear at very first sight that this was Germany’s fastest road-going sports car: the BMW M1 , 277 bhp strong, and well over 160 mph fast. That was indeed quite something, considering that BMW’s super-sports car had a price-tag back then in 1978 of exactly DM 100,000, enough for four BMW 323is plus a couple of optional extras.
Choosing the engine, BMW Motorsport GmbH initially focused on two concepts: Advance studies of Formula engines had led, inter alia, to a ten-cylinder code-named the M81, a V-engine with its cylinders at an angle of 144°. Suitably modified, this engine was also examined for its possible use in a sports car. But then the team around BMW’s Motorsport Director Jochen Neerpasch quickly opted in favour of a new straight-six, an engine concept supported by the excellent experience BMW had gained in the CSI races.
After all kinds of rumours with the grapevine running wild, BMW unveiled the secret in spring 1977, officially confirming the development of the new super-sports car. Then, in autumn of the same year, BMW published the first photos of the M1 in production trim, the car then making its first public appearance again half a year later: Together with TV presenter Dieter Kürten, Jochen Neerpasch proudly introduced the Group four version in the colours of Motorsport GmbH in a prime-time Saturday evening sports programme on Channel Two of German Television. And although this racing machine bearing starter number eleven was not yet ready to go, the first test drives were scheduled for April 1978.
Measuring 4,360 millimetres (171.7´´ ) in length, 1,824 millimetres (71.8´´ ) in width and 1,140 millimetres (44.9´´ ) in "height", the M1 exuded a genuine flair of power. And indeed, this mid-engined sports car was driven by a 3.5-litre straight-six fitted lengthwise in front of the rear axle and developing maximum output of 277 bhp. Code-named the M88, this engine was based on the volume-production six-cylinder combined with the four-valve cylinder head carried over from BMW’s CSI racing engines. Within this two-piece cylinder head, the lower section formed the combustion and coolant chamber, the upper half comprised the camshaft bearings and cup tappets.
The fuel/air mixture was delivered through three double throttle butterfly manifolds featuring six 46-millimetre individual throttle butterflies to the cylinders through two intake ducts per cylinder measuring 26 millimetres (1.02´´ ) in diameter. The all-electronic digital ignition system also reflected the latest state of the art.
Dry sump lubrication bore clear testimony to the sporting genes of the M1, the car being able to achieve a very high level of lateral acceleration. Fuel was supplied to the engine from two tanks right and left in front of the rear axle, each with a capacity of 58 litres (12.8 Imp gals). From the engine power was transmitted through a ZF five-speed gearbox connected to the engine by a two-plate dry clutch. The final drive differential came as standard with 40 per cent locking action.
The six-cylinder power unit was smooth and free of vibrations throughout its entire range of engine speed, even remaining quite docile at lower speeds. But this changed instantaneously once the rev counter hit 5,000 rpm, the M88 pushing the M1 forwards up to its top engine speed of 7,000 rpm with power and energy making even the most jaded car testers wax lyrical: "Once the throttle butterflies are fully open you feel a tremendous kick from behind continuing well beyond the 200 km/h-mark. There is no need to shift to fifth gear, for example, until you reach a speed of 213 km/h (132 mph) and from there you continue to accelerate up and up to the car’s top speed." Which, as recorded by Germany’s leading car magazine in autumn 1979, was 264.7 km/h (164.1 mph). Acceleration from 0-100 km/h in 5.6 seconds also looked very good, which is not surprising considering the power-to-weight ratio of 4,7 kg/PS, making things relatively easy for the 204 kW (277 bhp) engine.
The M1 was conceived and built for racing right from the start, the elaborate suspension with double wishbones on each wheel, gas-pressure dampers and two anti-roll bars remaining in command throughout the car’s entire speed range. With the exception of the more comfort-oriented response of the moving parts and the modified spring/damper setting, the road suspension was identical to the chassis and suspension on the Group four racing version. Four inner-vented brake discs ensured phenomenal stopping power from any speed and the front axle came with 30 per cent anti-dive minimising body movement even when applying the brakes all-out. Tyres measuring 205/50 VR 16 at the front and 225/50 VR 16 at the rear, finally, were certainly very big and muscular in those days.