the black powder is coming from the tail pipe not the belt. I need to know if anybody can tell me what makes the motor pre ignite. I pulled teh plugs and they look like charcoal gray to light milk chocolate color. I can also feel the plug wires jump when I hold them. The timeing on this motor is TDC. I have never seen a TDC timeing setting before. Tyler, I dont think I need to take the head off for pre-ignition. Thanks for trying.