struck my traxxas xl-5 esc with a spent jrl 7.2v pack and probably got 12-15 mph out of it. then I hooked up my traxxas 7 cell pack and the difference was amazing even just spinning the tires off the ground. wish the pack fit because i would have probably gotten 30+ out of it. in my stampede 4x4 that 7 cell is ok but my 8 cell packs broke shafts every time so probably could get 40 mhp out of it if that fit...i don't wanna dremel through my chassis but its so tempting.