There is rumor of a company in the Eastern US that sells modified BMW V-12's in the 6 liter range as far as adding turbos to a 750 where would you put them? maybe one of those new hydralic driven super chargers that might work. CRP has made a kit to convert the BMW v-12 to kit cars, you could buy one and stick paxton superchargers on the engine, that would be very HOT. Where to get the 4 valve heads who knows. Find the BMW part number for the special McLaren 6.0 engines and order one as a replacement? of course then you need the engine control chip too, and the turbos, and the exhaust. Might be better to just keep the 750 stock, and buy a race car for the track. Just some thoughts on the subject.