I am new to all this stuff and I am not a mechanic although it seems I am starting to be. I bought a 91 GTA 5.7 liter for $1000 that I am fixing up and would like to put headers on it and was looking at these because budget is a concern.

http://cgi.ebay.com/ebaymotors/1982-...#ht_4425wt_942

I noticed in the stock manifold there are all these small tubes coming out of it going wherever. Where do those go once headers are put on?

I also just want to use headers that mount straight down to my stock Y or whatever the hell is down there which goes to my 2 cats into one pipe to the rear muffler.

I am seeing all the shorties and longs and have no clue what will fit and what needs to be changed. I am about to do the fuel Injector 22# from Southbay as well. Do I need to go with higher rated injectors if I do headers and a shorter intake. Like the k n n filter right off the throttle body?

Help me out?

 

Did you see the sticky post at the top of this forum title "Whats the best exhaust? Whats the best headers?" That contains most of the info you'll need.

The tubes coming out of the stock manifolds are for the A.I.R. system. Its part of the emissions control system and required by federal law to be there on a street vehicle in the United States. You want to look for a set of headers that include those.

The most popular choices are Edelbrocks, Hookers, Hedmans, and Dyno Dons. Dyno Don is a member on this board and you'll find info on his headers all over this Exhaust forum.

Unfortunately, no headers currently on the market will bolt up to the stock GM y-pipe. Headers and y-pipes are a matched set from the manufacturer and install together.

You should not need higher rated injectors until you do a head and camshaft swap. Simple bolt ons will not confuse the computer. And some people, myself included, are not a fan of the filter right on the throttle body because you are getting hot air right from the back of the radiator. Cooler air is always better, like from the factory Trans Am setup you have.

 

Thanks for the reply it really helped and I will look at the sticky. As for the intake, I completely agree with you and will keep it stock to get colder air with a k n n filter in the box, I think I just used that more of an example.

Also, is it definitely worth the money and having the headers done? Is there that much of a difference?

 

yes

I won't go into the volumetric efficiency explanation because you probably already understand that.

It's worth having headers just for easy access to O2's and spark plugs

and please don't ask about power gains. Do a search.

You won't get many excited answers about exhaust form old timers. The subject has been beaten to death on this forum because the newest 3rd gen is 19 years old so rest assured the horse has been beaten to death.

 

Haha gotcha thanks.