BMW’s next M3 will indeed have a V8, as expected. It will be lighter than the inline-six it replaces yet deliver 420 hp in European trim.
BMW’s artistic new engine:Slideshow.

March 23, 2007
Following in the heels of BMW’s unveiling of the M3 styling prototype at the Geneva Motor Show, BMW has released specifications of the V8 engine. And it’s a monster, as befits BMW’s engine-building heritage, with 420 hp and 295 lb-ft of torque in European specifications. All this in an engine lighter than the inline-six engine it replaces.
BMW says the engine will be redlined at 8,300 rpm. It will use variable camshaft control and low-pressure double-VANOS for what BMW calls as “optimum charge cycle, system offering full power and performance even with normal engine oil pressure.” Unlike mainstream BMW engines, this will have throttle butterflies – one per cylinder for eight total.


More...