50-60mph will brake it really quick.
That's not a true 8th scale, it's more of a longer 10th scale car . Fitting a true 8th scale system in there will ruin your clutch / spur gear in minutes.
What u can do though , fit a Hobbywing WP SC8 ESC and a 550 brushless motor. That's 4s power, more than enough for your buggy. Although running it on 3s will make more sense for your particular model.