Originally Posted by Uli_HH
BUT itīs real simple ... do you think BMW/M-GmbH would spend the money to develop (and produce) two totally different I6 engines of the same or nearly the same displacement side by side ... I would bet the simple answer is NO ... never!
Infact S5X series engines are totally different, block are bored and longer than std. M5X series and its made on castiron, Crank got bigger main bearings, rods are totally differend, all engine parts are forged and cylinder head is special too, you canīt bolt S5X cylinder head on M5X engine etc... Everything in engine is totally differend than standart M5x engine, so how can you say that they are only little modifed?