he heart of any BMW M5 is its powerful engine. For the 2012 model, that means the same 4.4-liter twin-turbo V-8 that produces 555 horsepower and 500 pound-feet of torque that's already found in the X5M and X6M. To increase fuel efficiency 25 percent over the V-10 in the 2010 M5, which was rated at a mere 11/17 mpg, the 2012 model will use an automatic start-stop function in combination with a seven-speed dual-clutch transmission. An Active M differential will be employed to split power between the rear wheels, which should improve handling by over-driving the outer wheel in a turn. BMW assures us the M5 has large enough brakes to lap the Nürburgring right from the showroom. When it arrives next year, we will, of course, verify.
