All the 1/8rh scale cars are going to run approximately same speeds. In the neighborhood of 65-80 mph depending on which engine/pipe combo you use and of course what gearing you use as well. These cars are about as fast as they come.

Have read that the .21 fusion was clocked at around 81 mph by one of the magazines, I think R/C extreme maybe. This is probably your best "bang for the buck". I think this is around $380 WITH the engine. You'll easily spend double that to get an 1/8th scale onroad with engine.

Only drawback to the Fusion, which is a 10th scale, is it has tiny wheels, like all 10th scale touring cars and is easily upset driving in parking lots and streets. You'll need a really smooth surface.

I have a Schumacher XTR stadium truck with 3 speed. Lowered it, adjusted the suspension for onroad and put larger onroad tires and it friggen flys. Clocked it at 65mph so it's not quite as fast as the fusion, but it is waaay easier to drive and doesn't spin out or flip everytime you hit a pebble.

With a hotter engine and better tires, I'm sure I could hit 80 mph with it.