I have recently bought a 224 predator harbor freight crate motor.i have a munkuni v22 header, aluminum flywheel,racing plug, governor delete,125 main jet,oil low delete, and it's sluggish \ surging on acceleration,if I feather it I can get it to sometimes pick up only to hit a wall around 4k then crackling backfire type sound... pulling the plug it's carbon fouled but just on one side half the time.. I'm getting frustrated beyond words with this carb..