exhaust

[GtOfDeath]

I went to get a high flow cat on today and the guy told me it isnt going to do much for the car with out a bigger header pipe. Now where would I go to found 2.5" header pipe for a 1998 Grand Am Gt.

[95-GT]

Header pipe? Do you mean the down pipe?

[GtOfDeath]

Its the pipe that comes off the Manifold and gos into the cat. I know the guy told me its called the header pipe.

[Colin]

The stock manifolds and downpipe are the two main restrictions before the CAT . Unless your engine is fairly modded it's not gonna do much by just changing the CAT alone .

[GtOfDeath]

Thats why I'm looking for a bigger down pipe. So I can go with the cat and run a nice 2.5 set up of pipe back to the mufflers. I'm going to call around and see if I can found someone that will bend a pipe and make a down pipe for me.

[litdevil316]

i'm not sure, but someone might be able to custom make the pipe. go ask around at the muffler shops.

[voyager]

yeah, um, have them bend one for you. the problem would be the right size flange. i know my 2.5" flange came from some pickup truck..

the downpipe isn't something you can go pick up - you'll need to have a shop make it when they put in a 2.5" cat, 2.5" muffler, and hang 2.5" pipes to go with them.

[GtOfDeath]

I have called some shops today to see if they could make one and noone will do it. They say it will be to hard to bend a 2.5 pipe that much to work. Sooner or later I will found a shop that isnt scared to play hehehe.

[GtOfDeath]

Will I ready have the job hafe done from when I put the mufflers on before. I have 2.5 pipe started I just need to found someone to get the rest done. I need to get the down pipe the cat and from the cat back to the y done. I can get the high flow cat and the rest of the pipeing done for $150 but the guy said it waz a waste of money because the down pipe needs to be done first.

[Colin]

A better exhaust system from your existing Cat back will make a difference , it won't be a waste of money and may be all you need if your engines near stock . Forget about the High Flow Cat , unless you do the downpipe as well . ;)

[Old Guy]

I think you need to take a step back and evaluate what you want to do with that engine. In my opinion, if you're doing nothing more than maybe a CAI 2.5 is too much. The bottom end will be shot to hell.

I agree with Colin...forget the high flow cat.

[GtOfDeath]

Will with the engine I have done work to. Like Port & Polish MAFS, I did some work to the Throttle Body and I did the air fliter. I have the exhaust started and now I have the money so I want to get that done and out of the way.

[96gtcoupe]

Would a 2.5 exhaust with 40 series flowmasters be real loud or will it growl nice but not rice loud inside the car? This would be in a gt set up also.

[Cobra^R]

40 series is flowmasters loud series. I had it on my 4.0 ranger and it was loud for a v6, inside and outside