ok, been reading more tonight... I want to do the preheat system, but i'm not sure what type of tubing to use (that would transfer the best heat) and somehow i'd have to weld it around the muffler and then weld it into the exaust.... so whats a good flexible metal tubing i could use? what about the copper stuff people use for fuel tanks??? this'll be the tough part... if anybodys got photos of a preheat system that would be awesome...