It would still look like a fast car even if it was powered by a lawnmower engine. On the other end of the spectrum, there is a whole group of cars that conceal powerful drivetrains under the sheet metal of a normal car, like this lovely Ford Mustang V8-powered Rover 75 pictured. From high-horsepower MPVs to track-ready SUVs, we’re taking a look at some of the ultimate sleepers ever sold. We'll also tell you about guide prices for used examples today, and how many we think are left on the roads too: