A issue That i can see here. Could very well be if your still running the stock cam. When you install a bigger cam they normaly like a little more compression DEPENDing on how big you went with the cam ( the bigger the cam the more compression you may very well need)
So with the increase in compression the stock cam can not get enough fuel in or exhaust out in the lowwer rpm band to over come the increase in compression.? The headers may???? help this a little bit over the stock exhaust. But if you plain on installing a different intake and headers to start with You may want to thing about a little more cam then the stock one.
Hope this helps.}[oooooo]
Ps HOW about some more imput on this GUYS!!!! I'm sure I maybe a little off base here Seeing I'm no pro and I don't know everything. I may become a pro But I'll never know everything. We're always learning something new.
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NovaMan/Twisted6/Larry