gsx-r750 i see that everbody faild to mention the 1/8 scale onroad race cars. there a little exspensive but you get what you pay for. specs: belt driven 4wd chasis, .21 size motors(turbo plug about 3hp and 40k rpm)two-speed transmission, centax clutch(adjustable without tearing down)and foam tires(tons of traction and stabilaty on the right surface)
these are the f1 of rc!! 0 to 60mph 1.5 sec....top end about 80mph depending on gearing and combo. they are the most stable and able to handle the horsepower.(there race cars) but you need a track to drive them on other wise they just spin.
you will spend more trying to get a 1/10 to go really fast. these are top of the heap. none better. good luck