I JUST FINISHED A MONSTER TRUC AND I GO ONE OF THESE ENGINES OFF E-BAY CHEAP AND IT IS BRAND NEW. I THINK I NEED TO SWAP THE CARB I HIT THE THROTTLE AND THE TRUCK DOES NOT GO VERY FAST. I WAS ACTUALLY WONDERING IF ANYONE HAS A SUGGESTION ON WHAT SIZE OR WHAT MANUFACTURER CARB TO USE PLEASE I NEED HELP!!! I WAS ALSO WONDERING WHAT PIPE TO USE ANY SUGESTIONS?