you guys are probably gonna clown me, but what do you mean when you say plug chop? here in the very near future i am probably going to have to rejet my carb so right now i'm trying to get as much useful info i can find. while i'm asking, does anyone have an idea as to where i should start with the main jet size? all i have is pro design intake, holes in lid and pro circuit t4. also, i'm only about 400 ft above sea level.