Two prototypes of the upcoming M6 were spied testing side-by-side in southern Germany.

Our intrepid spy photographers have caught two 2012 BMW M6 Coupe prototypes testing side-by-side in southern Germany - one silver and one black.

As in the previous set of shots of the M6 Coupe, we get to make out some elements of that aggressive new front fascia and the rear bumper with an integrated quad exhaust.

As for what's coming under the hood, that will be far less of a surprise. The M6 will feature the same power plant as in the new M5 - a twin-turbo 4.4-liter V8 with 560 PS (412 kW / 552 hp) and 680 Nm (502 lb-ft) of torque. Gearbox will also likely be the seven-speed M Double Clutch Transmission which should make the car good for a 0-100 km/h (62 mph) sprint time of less than 4.5 seconds.