i have heard from many people the Maximum MT goes 31 out of the box, and if you add bearings, it would go even faster. The torq .16 engine it comes with has had some mixed reviews. Some loved it...some thought it was crap. I think its more of a matter of if you tune it right (not running it too lean, using a good fuel, air filter, etc.) but i really don't know of any engine upgrades for that truck. I don't know exactly what length of crankshaft, rear or side exhaust, etc. But people have given it overall good reviews if this car will be used just for fun and "bashing around".