As stipulated in the regulations, the cast parts in the engine block and cylinder head were adopted without modification from the production power unit. Both components were made in the light-alloy foundry at BMW Group Plant Landshut. Here, innovative and sustainable manufacturing methods are used to make technologically-sophisticated engine components from light-alloy casting.
Aside from the regulated cast parts, the engine in the BMW M8 GTE – containing approximately 2,300 further components, including 985 unique parts – required comprehensive modifications. Of these parts, 181 were derived from series projects, while more than 700 were specifically developed for the P63/1 or added from other BMW Motorsport racing engines. The engineers reduced the capacity from 4.4 to 4 litres, in line with regulations for the GTE class. The new design of the crank drive involved the implementation of a flat crankshaft, which brings with it the advantage of a regular firing order and gives the engine an even sportier sound.
The geometry of the combustion chambers, including the inlet and outlet ports, was also modified to ensure that the P63/1 is ideally designed for the demands of racing. Comprehensive modifications to the intake and exhaust system, and the complete redesign of the turbocharger, have also helped to improve efficiency.
Among other things, this results in the fuel burning very quickly and comprehensively at the optimal time, at a maximum temperature of over 2,100 degrees Celsius. This allows the P63/1 to achieve efficiency levels well above 40 per cent. This makes it the most efficient BMW racing engine ever in sports car and touring car racing. This efficiency gives teams far greater flexibility with regard to race strategy.
As well as being efficient, driveability is another outstanding feature of the P63/1. This helps the drivers get the most out of the BMW M8 GTE on the track. A completely new approach to engine control made it possible to achieve instant throttle response and linear power delivery from the engine.