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exhaust confusion

M.$tErNeR

New member
kind of new here and ive had my 1998 grand prix gt for around 3 months and ive been reading a lot of posts but im still kind of confused.hopefully someone out there has the patience to clear this up for me.the exhaust consists of the headers which run down to the catalytic converter which connect to a resonator which runs back into dual mufflers.a lot of the post on here talk about downpipes but im not sure wat the real benefits of a downpipe are or why there is resonator and then 2 muflers(seems like a ton of restriction to me).and there is only one catalytic converter on the 97-03 gt exhaust correct? im looking to give my car some good sound,or at least something to try and compare to my 98 camaro z28.lol so what are my best options,im not looking to spend a lot of money though.personally my best idea so far seems to be to just put an electric cutout on the exhaust piping before the catalytic converter but im not sure if its possible becuz theres not a whole lot of visible piping before the cat.so yeah i sort of have a lot of questions and a lot of confusion but im hoping somone can basically just give me some basic reasoning behind what most grand prix owners do to their exhaust and if my electric cutout idea has been done before/if any1 knows if that would work.thanks to anyone who had the patience to read all this.ur responses will be greatly appreciated.thanx

1998 grand prix gt
100% STOCK
84,000 miles
(parting out a 98 gt.no motor,hood or front fenders,bumper..everything else is available...pm me or send email to [email protected] thanx)
 


the exhaust consists of the headers which run down to the catalytic converter which connect to a resonator which runs back into dual mufflers.

Sort of. There aren't "headers" so to speak, but exhaust manifolds. These connect to a down pipe (which does exactly what it applies, goes down under the car). The down pipe has the catalytic converter as a part of it. This connects to the cat-back section which has a resonator and mufflers.

This link might help you visualize the exhaust better:

http://www.naioa.com/v2/modules.php?name=Forums&file=viewtopic&t=13427

a lot of the post on here talk about downpipes but im not sure wat the real benefits of a downpipe are

The stock downpipe is pretty constrictive since its a double walled design. A new downpipe gives you a more free flowing design and a better catalytic converter that won't eventually fail like the stock unit does.

or why there is resonator and then 2 muflers(seems like a ton of restriction to me).

It only needs one muffler, technically. But, since there are two exhaust exits on the GP, there are two mufflers. The resonator is a pass-through design and as such does not create a restriction. Simplest way to put it is the resonator helps keep interior drone noise down, and the mufflers help keep the exterior noise down.

and there is only one catalytic converter on the 97-03 gt exhaust correct?

Correct.

im looking to give my car some good sound,or at least something to try and compare to my 98 camaro z28.lol so what are my best options,im not looking to spend a lot of money though.

Good luck. A V6 will never sound like a V8. Closest I ever got was when I had a horrible exhaust leak at a manifold joint:

http://smg.photobucket.com/albums/v317/sabrewings/random stuff 2/?action=view&current=MOV02400.flv

personally my best idea so far seems to be to just put an electric cutout on the exhaust piping before the catalytic converter but im not sure if its possible becuz theres not a whole lot of visible piping before the cat.

Exhaust cut-outs can be more trouble than you think. The car is tuned for running with the cat-back, and if you suddenly open the down pipe up then the car will start to run lean as it flows more air. Lean = knock = tragic engine death.

thanks to anyone who had the patience to read all this.

Wasn't so bad. Some more spacing and a few different paragraphs would've made for easier reading.
 
thank you a lot.the best way to get a better sound then would be to obviously change the mufflers and possibly do away with the resonator??? what mufflers do you suggest then? i know a lot of people use the flowmasters but im not big on them and i dont know any online websites to grand prix parts so im kind of stuck here.what would be your best suggestion?

heres my camaro exhaust btw,but i know theres no way to replicate this sound with a v6.lol



YouTube - 1998 camaro z28 with slp lm1 catback exhaust
 
an electric cut out really shouldnt make the motor run lean though as long as it is put behind the sensors correct?? (which i believe are before the downpipe anyways) plus its not like im going to be running it 24/7 so i wouldnt think it would do that much damage.i mean theres plenty of ppl out there who use these on their vehicles all the time without any problems so how great could my risk be?
 
The cutout will suddenly make the engine move more air. The fuel trims it already had learned would now be incorrect and it will have to relearn the trims. It probably won't react fast enough and it will knock.
 


I've got an '05 GP GT and I'm looking for some better sound also. How about just swapping out the two rear mufflers with a couple of glass packs?

Would that do any good, or just be a waste of money?

-Ralphie
 
maybe just take the mufflers off altogether.glasspacks are very unrestrictive anyways.id be interested to see what they would sound like on a grand prix though.anybody have a set up like this?
 
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