It's been rumoured, but here finally is a spy photo of the 2013 Mercedes-Benz SLS AMG Black Series. Caught winter testing, the prototype has a wide body kit with a modified front fascia, revised sideskirts and extended wings. We can also see high-performance brakes and larger rear wheels, which hint at some changes to the rear axle as well. Under the bonnet, rumours suggest the 6.3L V8 engine could deliver 600hp and 677Nm of torque. This is likely to enable the car to accelerate from 0 to 100kph in 3.5 seconds and hit a top speed in excess of 322kph.