The new C-Class Coupe is impressive. And the 2017 Mercedes-AMG C63 Coupe shares very little with it. That's okay, though, because it improves on its lesser stablemate in a number of areas. Its exterior is longer and more expressive, with only the doors, roof, and trunk lid shared between the two, and the interior is upgraded with performance seats and sport-specific controls. But none of that will matter when you mash the accelerator and access the 503 hp coming from its AMG 4.0-liter V8 biturbo engine — the same one used in the AMG GT S sports car — on your way to a sub-4-second 0-60 time and a top speed of up to 180 mph. Available in standard and S variants.