[What's_nitro?]

Since it is "stuttering" at low speed I don't think excessive RPM is the problem. If it were stuttering at the end of a drag run, then that would be the case. Could it be a shorted winding in the motor? Kinda hard to tell, because you don't run long enough to really heat up the motor anyways.

Here's an idea. Drive around for a few minutes at a "normal" pace, maybe 35-40 mph, and see if the motor gets wicked hot. If it does then it probably has a shorted winding.