i have an 89 formula with a 5.0 TBI...within the next month or so it will have world s/r torquer heads, an edelbrock performer intake manifold, the caddy-buick intake setup, and either a modified TBI unit or an aftermarket one from holley. i am on a budget and i want 1 5/8 primary/ 3in collector headers with a 3in y-pipe...what are your recommendations?

 

Eventually, you will find that trying to save money in this area will lead to one of two things: Either spending more money in the end, or making less power.

Buy exhaust from one end to the other for '86-'90 TPI single cat application. I'd recommend the Hooker 2055 headers, Catco 9118 converter, and whatever cat-back for that application you want (with the possible exception of Pacesetter as one to avoid - not that it would be terrible, just that there is better for the same money). If you go with cheaper headers, especially one that doesn't have a y-pipe to go with it, you'll end up spending a bunch of money to have a y-pipe fabricated and it probably won't be nearly as good as the Hooker performance- or fit-wise.

Don't get any exhaust pieces for TBI application. It will be small and restrictive. The TPI application stuff will fit the engine and chassis just fine.

Of course, these changes you have in mind will require PROM changes.

 

five7 hit it right on. If you are replacing your exhaust all at the same time than you want to do just as he instructed. If however, you have to buy your exhaust in stages you need to buy the cat back that matches your engine code. That way it will have the necessary reducer on the end of the I pipe to attach to your stock cat. Then when the time comes to do headers, you can buy your set add a high flow cat and then cut the reducer off the cat back to achieve a full 3". This is always more work and it is just easier to wait till you have all of your parts before you replace the entire system on a TBI car.