BMW M8 (E31) Prototyp

The BMW M8 (E31) was conceived as a rival supercar that would have more power and higher top speed than a Porsche or Ferrari of the time. But, BMW management found it too expensive and unprofitable, primarily due to the ongoing economic downturn of the 1990s. Ultimately, the project was cancelled. The only assembled prototype was put away in a secret BMW M garage and was not mentioned anywhere. However, an exclusive article in the February 2010 issue of BMW Car Magazine revealed that the prototype M8 still exists. The car was first presented to journalists on July 2, 2010 at the BMW Museum in Munich. The only public display of the car took place on August 17, 2012 during the Autobahn Legends car show in Carmel, California, where the M8 was specially brought from Germany.

Mechanics

The prototype was powered by a naturally aspirated V12 engine modified by Paul Roche, dubbed the BMW S70/1, which had separate roller valve throttle bodies, four valves per cylinder, carbon fiber intake manifolds and continuously variable valve timing. As a result of improvements, the volume was increased to 6.1 liters, and the power increased to 550 hp, torque – up to 650 N∙m. At the same time, 90% of the torque was already available at 2000 rpm, which was not available even to Ferrari at that time.

There is a misconception that the M8 engine was installed in the McLaren F1. In the design of the F1, another refinement option was used – the BMW S70/2 engine – in many respects similar, but also, like the S70/1, originating from the BMW M70 engine.

While no official testing has been done, according to BMW, the top speed was calculated at 317 kph, and it was claimed that the BMW M8 could easily break the 320 km/h mark. The acceleration time from 0 to 100 kph was calculated to be approximately 4.2 seconds.

Exterior

By making elements out of fiberglass (such as the hood, doors and trunk lid), Lexan windows, using carbon fiber wheels, and removing the rear seats from the car, the car's curb weight was reduced to less than 1,450 kg.

Also, the M8 prototype received:

• new hood with vent and no retractable headlights;
• new front bumper;
• new rear-view mirrors;
• two air intakes in the flared rear wheel arches for cooling the engine and differential oil;
• wider track due to a wider drive axle;
• reinforced front brakes;
• M-System wheels with carbon center;
• central pillar in the cabin to maintain rigidity;
• bucket seats with four-point seat belts;
• additional instruments on the panel: oil pressure, oil temperature and water temperature sensors.

Sources