Exhaust FAQ - Please read before posting questions.

[Old Guy]

Exhaust FAQ (primarily 99+)



1. Who makes a Cat Back exhaust for a Grand Am?

At the present time only SLP and Borla make a bolt-on exhaust for the GA, but any good muffler shop can do a custom exhaust for our cars.

2. What’s the difference between Borla, SLP and custom exhausts?

Actually the only real difference will be in the sound. The HP gain will be very close with quality aftermarket exhaust systems.

3. How much HP will I gain from a Cat back Performance exhaust?

Typically about 8 HP depending on what other modifications if any you have done, but it will enhance any further mods you do.

4. Will I gain HP if I just replace the muffler?

Probably a little, but it won’t be a noticeable difference.

5. Should I remove or replace my Catalytic Converter?

Unless it’s bad there’s not any real advantage to replacing your Cat with a high flow Cat unless you have done major modifications. The stock Cat is not really very restrictive.

5. What size pipe should I use?

Typically most guys will use 2 ¼” or 2 ½” pipe. Anything more will result in too much of a loss in back pressure unless you have done some major modifications.

7. Can I put duals on my SE?

Sure, just do it the same as a GT. Any transverse muffler will work the same on either car.

8. How much should I expect to pay for an exhaust?

Borla will probably be the most expensive at about $600.00 U.S. going down to about $300.00 for a custom exhaust, depending on which mufflers you use.

9. How loud are the different exhausts?

It all depends on what you think is loud. SLP will probably be the loudest except for straight pipes, which I wouldn't recommend. Borla would probably be the quietest with everything else falling in between. Before buying a system I would listen to as many as possible because once it's on it will cost you more money if you decide you don't like it. Typically exhaust systems will sound different after a thousand miles or so and will mellow over time.

10. Do I need to keep a resonator on my exhaust system?

No. Just remember that without it there will be more cabin noise. The stock resonator can be replaced with a straight through resonator that will not restrict your exhaust in any way and still reduce the cabin noise.

11. Can I run duals straight out of my exhaust mainifolds or headers on a V6?

While it's possible, there are a few things that you have to consider. There isn't much room to do it, you'd need two catalytic converters, and the HP gain will be minimal if any. The loss of any back pressure would probably hurt you more than help you since you'd lose torque in the low end.

Heres a great article on pipe size rel;ative to engine size and HP. From the chart included you can determone what size of tubing best suits your application.

Pipe Size Article - Bigger isn’t always better. (http://www.dynomax.com/techsupport.stm)

[MasonGT_2000]

Which would be a better choice? I'm stuck between a Borla and a Flowmaster 50 series duraflow muffler (both are 1 inlet, 2 outlet) I'm looking for a deep aggressive sound (as close to a trans am sound that I can get out of a 3400 V6 w/ ram air) Any comments will be greatly appreciated.

[airdog_icp]

i have a flowmaster 30 series delta flow on my GA, i often ask if i had a v-8 put in it from the sound (i live in retardsville), but a sound of a trans am is hard to replicate in a v-6, now as to the cat, i have taken it off, and picked up half a second on my 1/4 times and almost 5 MPH, so if your willing to beak the law, or put on a hi flo cat, itz up to you

[Murph2003]

If you completly took out your cat what did you do with your oxygen sensor I always thought you couldnt take out your cat because it would screw up the computer and make the car run like crap. Thats what i was told anyway

[azeniskid]

backpressure isn't the proper term... it's exhaust gas velocity... you're looking to get the gasses out as fast and as efficiently as possible. straighter flow better flow.. freer flowing is better flowing.. however too large a diameter is not..


you should also note that the

borla is 2.25 inch while hte slp is 2.5inch.

[airdog_icp]

well i just finished putting on my new exhaust, i bought a moroso muffler, and hollowed out the cat ( so itz there if any law dogs that check ) but i have it running out on the side in front of the driver side tire, havent ben to track to see any improvement, let you know,

as for the O2 sensor, i bought those O2 simulators, to turn off the SES light, but it ran 15.8, without them runs 15.4, so im willing to have that light for the added performance, the down side is i have less fuel milage, but other than that, i runs great

[AznGA]

Originally posted by airdog_icp
well i just finished putting on my new exhaust, i bought a moroso muffler, and hollowed out the cat ( so itz there if any law dogs that check ) but i have it running out on the side in front of the driver side tire, havent ben to track to see any improvement, let you know,

as for the O2 sensor, i bought those O2 simulators, to turn off the SES light, but it ran 15.8, without them runs 15.4, so im willing to have that light for the added performance, the down side is i have less fuel milage, but other than that, i runs great
Are you sure the O2 sensor slowed it down? I mean there are a lot of factors at tracks......

[LordRayden]

7. Can I put duals on my SE?

Sure, just do it the same as a GT. Any transverse muffler will work the same on either car.

you can't put duals on the 2.4L can you?

and if not duals is there any exhuast kit for the 2.4L 'cuase I havn't found any yet, they are all for the 3400..

Can someone please give me some insight?

[Matt95GT]

Originally posted by LordRayden
you can't put duals on the 2.4L can you?

and if not duals is there any exhuast kit for the 2.4L 'cuase I havn't found any yet, they are all for the 3400..

Can someone please give me some insight?

You certainly can. It's simply just dual outlets from the muffler, the rest of the stock exhaust systems are the same.

The GT exhaust will work on the 2.4 (although not much to gain), the Borla cat-back kit for the GT works on the 2.4 SE and sounds decent. I'd stay away from the SLP kit, it sounds fairly bad on the 2.4.

[Bjornboy81]

EDIT: beat me to it Matt :)

I believe the SLP cat-back will work on the 2.4L

As far as the duels thing...they all have a single pipe back with a one in/two out muffler (camero style) so yes you can but duels on a 2.4L :) I believe it was tenspeed that put the SLP with duels on his 2.4L

Anyways, here's a thread on it http://www.gaownersclub.com/forum/showthread.php?threadid=46268

[LordRayden]

Thx guys

[JustinBTE]

quick question guys, I have an Iceman CAI (well techincally WAI) and then just a Bosal prosport muffler. between the two are they going to do any much more horsepower gain rather than just having one or the other? Like are they going to coincide and work with each other to add a little bit more horse?

[LordRayden]

.

[Brandon]

i changed out just my muffler, and i can tell theres a little more power.. not alot, but it is noticable.

[cx8219]

I recently had a shop put custom exhaust on my GA SE. Any F-Body muffler will do the job. They put a stock Camaro muffler on and it sounds great. I didnt want the loud rumble in the cab. The F-body one does the trick very nicely. A little rumble at idle. A little resonance in the cab up to 2100-2300 rpm. After that you dont know it is there. I have my 5 year old in the back a lot and didnt want too much. Very nice fit and only $150.00 with tips and all.

[Pizzon]

quickie, i have dual exuasts on my GA, but they really aren't true duals. (main pipeing goes into one muffler, then a small pipe goes from one muffler into a smaller one on the passsenger side).

I want a more true dual, but should i just split the pipes after the cat into 2 muffs or just run 2 exuast pipes with 2 cats?

[Old Guy]

First of all there's really not enough room under the GA in order to properly do it and secondly, you won't gain a thing performance wise. Plus they still won't be true duals. The only real dual exhaust is when you run a system straight off of each manifold, and again, there will be no performance gain.

[sush]

Hi,

I’m upgrading my pipes to 2.5” and I’m getting the Dynomax Super Turbo muffler,

About the resonator...
Should I:
- leave the resonator in there?
- put a new dynomax high flow glasspack (2.5” in and out)
or: - remove the resonator, and just use pipe?

I'm looking for a low, smooth sound, nothing too crazy, trying to get as many horses/torque as possible out of the car.

[Burger]

I have a 2000 Gt. I was looking and decided that i want to put a Y off of the resonator and have two pipes on each side of the car, under the door (I have never seen it before).
1. Will this effect the back pressure to damaging the engine?
2. How loud would it be? Should i put a small muffler on it anyways?
3. Any cheap ways in bending exhaust pipe?
4. Any cheap stainless steal exhaust tips

[sudden_impulse]

1. As long as you have the cat and resonator on there shouldn't be problems with backpressure.
2. It will be loud, but try it without anything and if you don't like it you could swap the resonator out for a small turbo muffler or something.
3. Pressure or mandrel? Pressure is easy, go to a shop and ask for bends. With mandrel you could try a shop but your best best would be to buy the bends off Summit or a parts store like that.
4. Define cheap, and what kind of tips are you looking for, single, double, straight, angle, etc. They change the pricing. I've found ss dual tips for like $50 per.

[Atlas98]

I'm thinking about buying a Borla Cat-back exhaust and from what i've read it sounds like it will work fine, but i'm just double checking before i decide on spending 800 dollars, if it will fit what mods will be required(if any). please pm me if you have an answer to my question

[Realrider88]

I still dont understand if it is a good idea to upgrade to a custom cat back exhaust system, is the stock one ok? Will there be a significant increase in H.P. with the custom cat back? Or is it just better to get a new muffler?

i saw the Aero Turbine Muffler AT2525 on http://www.mpracing.org is that i good idea?

or is the Grand Am Pacesetter Cat-Back Exhaust System on http://www.mpracing.org a better idea?

or any better ideas than both of those ??

[Blackhawk]

Look around, there are plenty of clips of the Flowmaster 80 cross-flow or a few of my car:
http://i111.photobucket.com/albums/n134/sudden_impulse/Exhaust/th_Exhaust.jpg (http://s111.photobucket.com/albums/n134/sudden_impulse/Exhaust/?action=view&current=Exhaust.flv)
A cat back is going to give you better sound, a little more HP, lets your engine breathe better. If you upgrade the size then you might lose a little low end, not too much but it slightly shifts the powerband to the higher RPMs.

[Realrider88]

noob question.. isnt there already a cat back stock? so a new one wouldnt make much of a difference? and you didnt tell me what the best way to go is... muffler or new catback about the ones i posted above

[Matt95GT]

noob question.. isnt there already a cat back stock? so a new one wouldnt make much of a difference? and you didnt tell me what the best way to go is... muffler or new catback about the ones i posted above

There are literally hundreds of exhaust threads... start reading. Summary: the purpose of changing the cat-back piping is to upgrade the size and smoothness of the bends for better flow. The muffler alone does close to nothing.

[Realrider88]

sorry i thought this is all the threads about exhaust.. im still trying to figure the site out, how it works

[awfulwaffle]

I was under the impression that stock GT piping was 2.25". If that's true, where is the performance benefit in the Borla exhaust?

[sunrunner_pei]

I was under the impression that stock GT piping was 2.25". If that's true, where is the performance benefit in the Borla exhaust?

Mandrel bends and a higher-flowing muffler. But the Borla probably offers the least performance upgrade over other systems. It's a high-quality system with a very nice mellow rumble, but it's often said to be too quiet.

[apmurphy]

Anyone have pics of their car on a lift that show the exhaust set-up? I don't have a lift but wanted to check out the exhaust route and work out some ideas.

[gadragon]

so flowmaster 80 is the highest used muffler it seems on here. are there different sizes of the flowmaster 80 or is the 80 only coming in one size of 2.5 inch.

[PORTMAN96]

I called a few muffler shops today. They said kits for a 96 2.4l se is rare, they said they could put a custom exhaust on...I want it to be loud, and better performace,what should i tell them i want done?

[Matt95GT]

I called a few muffler shops today. They said kits for a 96 2.4l se is rare, they said they could put a custom exhaust on...I want it to be loud, and better performace,what should i tell them i want done?

Have you searched at all? There are tons of threads dedicated to this exact topic.

http://www.gaownersclub.com/forum/showthread.php?t=85365
http://www.gaownersclub.com/forum/showthread.php?t=77025
http://www.gaownersclub.com/forum/showthread.php?t=77022
http://www.gaownersclub.com/forum/showthread.php?t=69574
http://www.gaownersclub.com/forum/showthread.php?t=67543