Not sure if i read it rite, but, if you put a GYT kit head on a standard ported DT1 cylinder i don't think you'd have to change the [std carb] much [if at all]. I did try that once on a fairly worn piston port DT1 but just made the rattly piston rattle worse. In saying that, i probably never knocked the timing back a bit [40 odd years ago!!], in those days i used to think more was better [advance]--slow learner 'me'. Standard DT1 pipe might be strangling it so far as making use of more power [high com] which might be just creating more 'heat' [as i think you said]. I'll stop there thanks just in-case i have my wires crossed & heading off track [good at that]. Cheers. ps, higher com needs higher octane fuel too of course.
