You already have headers on there, so up grading to more expensive ones is not going to net you any power increase in your situation. Neither will wasting money on roller rockers when stockers are doing the job just fine. There is no hp upgrade to roller rockers, they are just more friendly on valve guides when used with high lift cams. They also offer a truer rocker ratio, but not worth the $$$ for you. If you want a bolt on upgrade that will do something, save your $ for a used centrifugal supercharger.