According to info I have S85 V10 engine is able of more than 400kW - more than 544HP.

And it will be offered in CS / CSL M5 & M6.

So around 109HP/L.

Which leads us to 435HP for 4.0L V8. But since M3 always gets creme-de-la-creme engines, I wouldn't be surprised if they could squeeze 460HP out of it (in CSL version).

So this paired with aggressive gearbox, killer suspension, ultralightweight material used, amazing steering the new M3 will be a new benchamrk in its class. Mind: BMW have Porsche 911 & AM V8 in mind as M3 coupe competitors this time.