Such is the level of modification required to transform a regular BMW 3 Series into an M3 that it is hard to see how the company ever makes a profit from this vehicle.
The base shell is carried over from the regular car, but remember that M division can make requests for particular reinforcements at the initial design stage. To this is added a set of bespoke aluminium suspension components whose only commonality with the base car at either axle is a pair of rear lower wishbone control arms. This saves 2.5kg and gives a much stiffer platform for wheel control.
For the external panels, only the door skins and light units remain. Thermoplastic bumpers and front wings house front and rear tracks 38mm and 31mm wider than a 335i and the bonnet is pressed aluminium.
The coupe and saloon use a carbonfibre-reinforced plastic roof to lower the car’s centre of mass. Over a glass sunroof-equipped car the saving is 22kg, although that figure falls to around 5kg over a regular steel panel. The convertible’s roof arrangement adds more weight, at the slight – but evident - cost of handling precision.
Just two cylinders of the M3’s V8 sit ahead of the front axle line. Displacing 3999cc, the engine produces 414bhp at 8300rpm and 295lb ft of torque at 3900rpm.
According to BMW, it uses the most advanced engine management computer in the car world, it is claimed to be more fuel efficient than the straight six it replaced, the block is 15kg lighter and it uses brake energy regeneration to allow the alternator to decouple under hard acceleration, yet charge more efficiently at other times.