I thought about mine a little more and I do remember having carb problems with it. I ended up running a carb of off one of my C6's and that made the tune a lot more consistent. I would check for the crack in the block like CHAOS says tho because I know what most people do with a Revo (same thing I used to do) and really hard crashing/cartwheeling and huge jumps can and will crack a crank case.