I don't have any experience with headers myself(getting one soon though), but I do know that if you want to keep some low end, a 4-2-1 is what you want. The 4-1 is more of a race type header and frees up more air flow, thus improving high end. JohnAOL IM: John99RSjohn99rs@hotmail.comhttp://johnseclipse.homestead.com
http://www.cardomain.com/ride/3130861