first off i gata say, thanks for all the help so far guys. oks so right now i have a 1988 camaro 305 TBI (L03) with an open element air filter on it, it also has a Flowmaster American Thunder dual outlet exhaust that the previous owner had put on. so my 2 questions are what headers(as specific as u can be) can i get for my car that will fit with no mods needed, and with those headers do i need to replace my flowmaster system and if so what should i get? thank you

 

Your exhaust is comprised of 3 parts. You have the headers and Y-pipe, the catylitic converter, and the cat-back (muffler portion). What you have is just the cat-back. Therefore you have the stock cat. Make sure in fact that you have a cat-back and not just a flowmaster muffler. You want the increased pipe size that cat-backs have. You will easily be able to tell this by the diameter of the pipe. It shoul dbe near 3". If it does you are one step ahead of the game. If you do have a cat-back than you will most likely have a reducer on the end of the main pipe so that it can connect the 3" piping to your 2.25" stock cat. You can peer under the passenger side seat to see where this conjuction is.

From here you have one of two choices. You can either replace the cat and the manifolds or just replace the manifolds with headers. I would choose the later. All kits "specifically" tailored for TBI applications have the same 2.25" pipe size with the apporpriate reducers and connections to mate to your stock cat. This fine for installation but you are not gaining much over the stock equiptment. It is tough to justify that kind of cost for minumal performance gains (and future power making potential). Your best bet is to buy a TPI specific header set so that it comes with a 3" y-pipe. Everything will bolt up the same way as if they were TBI headers but they won't have the tiny piping. You can then pick up a universal or direct fit TPI 3" cat. You would then have to cut the reducer off of your current cat back and join your new headers/y-pipe to the cat-back via the cat.

I hope I am not confusing you.

Should you choose route one and keep the stock cat with the small piping your only choice for a direct fit kit (no header kits are true 100% bolt on) would be the edelbrocks. They leave a lot on the table as far as performance is concerned.

If you are more performance orriented and want a better header than look at the mac's, hooker 2055's or SLP's. They will all have 3" piping and have the best overall design.