This is one of the first cars to feature AMG's newest engine. This 5.5 litre V8 not only produces 415 horses and 398 ft/lbs of torque, but also features cylinder deactivation to make this one of the world's most efficienct V8s. The engine will shut off cylinders when the engine is not under heavy load, such as when coasting or braking, or it can be manually put into four-cylinder mode, where cylinders two, three, five, and seven all shut off. When operating with only four cylinders the engine still produces a respectable 170 ft/lbs of torque. All this means that you'll be able to hit 60mph in 4.5 seconds and get 28mpg. Not too shabby.