You need to go back to the stock shims 1st. How much fuel do you have through there if you have less then 2 gallons you should have all the stock shims plus the copper extra that came in the box in there too. The 5 port should have more than enough bottum end for anyone. I also would go to a warmer plug as they like them better in my eyes P3 or 4 or OD 77T or 97T. And I am not shure what your looking for with that pipe header configuration do you have the stock header if so put that on there. I run racers edge heat shield tape on all my bodies just because I spend alot of money getting them airbrushed its safe and I like that.