How do I do this??? I need to dial out the overlap or as much as I can because I am using the NOS kit. Do I need to retard the exhaust and advance the intake? Advance the exhaust and retard the intake? Or is it the total opposite like retard both intake and exhaust or advancing both??? I need help soon guys, the races start this Saturday and I have the last appointment at the dyno on Friday. I am running a 125 shot on the NOS kit # 02040 and on the dyno I am only gaining 73 hp. I think that I am losing the other 50hp thru blow-by, because of both intake and exhaust valves being open at the same time.