So the people at bmw think that the previous m550d (non uk) didn't have enough turbos (3), so they've gone quad, that's outrageous but also bloody cool at the same time, I like it when engineers go crazy... i bet someones won a £5 bet somewhere...
http://www.autoexpress.co.uk/bmw/5-series/99295/bmw-m550d-xdrive-revealed-with-four-turbos
http://www.autoexpress.co.uk/bmw/5-series/99295/bmw-m550d-xdrive-revealed-with-four-turbos
