i got a maximum st for free and the engine was a trq.12 and the pistin was worn bad, no spur gear, no wheels, no pull start, no air filter, no throttle linckage, shocks screwed up, no lug nuts, so i ended up buykng a torq 16, and put a muffler on it from a nitro rustler pro.15 the stock muffler, runs like hell, fast acceleration, i love it