The new 2013 BMW 6 Series Gran Coupe, a four-door, four-passenger sibling to the 6 Series Coupe, arrives late next summer in the U.S, aiming at its competitors as the Audi A7 and the Mercedes-Benz CLS. Available in three models The 640i Gran Coupe, powered by a twin-turbo 3.0-liter inline-6 rated at 315 horsepower and 330 pound-feet of torque that hits 0-62 in 5.4 seconds. And the 650i Gran Coupe and the all-wheel-drive 650i xDrive Gran Coupe, both models feature a more potent variant of BMW's twin-turbo 4.4-liter V8, 0-62 less than 4.6 seconds in either model. All three 6 Series Gran Coupe variants use BMW's eight-speed automatic transmission, and all have top speed restricted to 155 mph. Other features include adaptive LED headlamps, Active Roll Stabilization, Integral Active Steering, active cruise control, night vision with pedestrian detection, and a Bang & Olufsen surround-sound audio system.