Whatever works for you man and I port match everything the best I can but have heard there's very little gain or loss by a slight mismatch. I don't buy that myself and know for sure first hand that the wrong header can be worth LOTS of power when the top flange is in the roof of the port a 1/4" as it was on a guys sb Chevy I messed with. When he put on the correct headers, the car picked up on motor and spray and the et's went down...........