This has to be one of the best exhaust noises we've heard in a long time. The reason behind the cat's loud roar is a supercharged V8 engine, which spits out 550 hp and 680 Nm of torque. The 2012 Jaguar XKR-S is the top of the line XK model, which is able to get from 0 to 60 mph in 4.2 seconds. The carmaker says that the 2012 XKR-S is the fastest Jag they've ever made.