The_Phoenix

iTrader: (3)

I am going to own an '89 Trans Am GTA soon and the 1st mod I wanna do on it is put a full 3 inch chambered exhaust all the way from the headers to the back with cats; any suggestions with this setup? should I do it? the car already has flowmasters but the sound that the chambered exhaust lets out sounds much meaner and bieng that its a 3 inch, it should sound much more wide open right? I also heard that its the best flowing exhaust out there...let me know what you guys think...later!

DaSkinnyGuy

Absolutly do it and pick up a high flow 3" Cat it will help flow and sound. great choice. Are you doing true dual or a signle cat back?

The_Phoenix

iTrader: (3)

I want to go with the true dual setup! Ita gonna be pricey but its gonnabe worth it

DaSkinnyGuy

Once its together can you get us a nice sound clip video of it.

1991CamaroRslow

iTrader: (3)

I would advise against a true dual 3in setup. Just do a single 3in exhaust with a single muffler, or do dual 2.5in mufflers. Dual 3's is overkill and it's harder to tuck than dual 2.5's.

The_Phoenix

iTrader: (3)

It won't be for a while until I get the system put in but I'll definatley post an audio clip of it! How much ground clearance would I need to put in the 3inch setup? Does it affect performance as well 1991camaro? I know its gonna be loud but putting in the cats is gonna mellow it out a bit so Im not too worried about that.

Thanks,
Ruben

urbanhunter44

iTrader: (3)

A chambered exhaust setup is among the sweetest sounding of all. GMMG and Stainless Works both have catbacks that will work. Be prepared to drop some coin though. They're between $750 - $950 depending on what you want.

An easier route to go is a true duals setup. $200 in parts from Summit Racing and another $200-$300 for the labor and you're set. Granted you have **** for ground clearance however...

Reid Fleming

iTrader: (2)

You know my answer on the chambered idea.

I agree. A single 3" chambered flows like crazy. I noticed a difference in power after I went GMMG. It revs quicker. But dual 3" is too much unless you're making I'd say over 400 HP.

The bends in the GMMG aren't that sharp. Not like going into a muffler and having a tight 180° bend in there before it comes out the tailpipes.

I thought about going dual myself. But bad ground clearance is just a nuisance.

The_Phoenix

iTrader: (3)

Cool! Thanx for the info guys! I would still like to know in what way does putting in a full 3' setup affect performance? I posted some pics of the car under the "Body" section titled "is this a real GTA???" Later!

1991CamaroRslow

iTrader: (3)

What do you mean by a "full 3in setup"? A full 3in single exhaust setup will be killer. I have a set of dual 2.5in classic chambered's on my car running from Hedman long tubes. I got the mufflers, headers, S bends, H pipe, and labor all done for under $400 total. The ground clearance isn't so bad if your car isn't lowered, I still drive mine around and it is lower than stock but I don't know exactly how much (adjustable coilovers). There's no sense in running a pair of 3in duals, I can't say for sure that it'll hinder your performance but it's a waste of money for all but the most powerful setups. Dual 2.5's or even dual 2.25's should be absolutly fine until you start doing around 400rwhp. The best way to go is to run a set of shorty headers, a good 3in Y pipe, your cat, and after the cat run the muffler and a dump in the channel where the pipe normally runs. This'll be cheap and effective.

The_Phoenix

iTrader: (3)

What I mean by full 3' is that all of the pipes will be 3' in diameter straight thru if possible but if its not possible, I will run a 2.5' or 2.25' setup like reidflemming has on his 89 GTA in the exhaust section of this forum. L8r!

The_Phoenix

iTrader: (3)

Hey I asked the owner of the '89 GTA that I'm gonna buy to send me a sound clip (ended up getting a video clip) of the car's flowmaster exhaust and here it is from the interior and then from the
outside http://youtube.com/watch?v=JQ3EBbfm8vU....any one know what type of flowmaster muffler/s it is?


Thanks

The_Phoenix

iTrader: (3)

what did u think of the car?

The_Phoenix

iTrader: (3)

MrBrooks

If youre not making real big hp numbers(400+rwhp) you will do well with one of these. http://www.classicchambered.com/classic/products.html The medium size should be able to run where the straight section of pipe along the trans tunnel is on a stock system then have the exhaust shop make a y after the rearend into 2 pipes so it will look rite. these thing flow STOOPID numbers and you can save your self a TON of cash over the GMMG setup. you can probably run this for about $400 or less(thats if you already have the headers and y-pipe to tie into). $58 for the muffler and then the pipe and labor at the exhaust shop.

The_Phoenix

iTrader: (3)

Thanx for the info mrbrooks...I actually want the car to push about 700hp+ with other mods of course...will those meduim pipes still be suitable for such hp? Also you mentioned that only one pipe is enough....wouldnt 2 flow better? Im not worried about the loudness since i will be running cats as wel.

Thanks for the advice,
Ruben

MrBrooks

If you are going to be making that kind of hp then you will need to run a duel setup. What i meant was that one(1) would be good to 400ish rwhp. Do you want to run a full system out the rear or just dump at the diff?? Either way these things as I under stand are with in 50-75 cfm of a straight piece of pipe but still offer substancial sound attenuation. If you are going to run twins off of long tube headers then you could use the large version(the longer you make it, and farther away from the header you put it the quieter it will be.

The_Phoenix

iTrader: (3)

Yeah the idea of running a true dual 3' chambered setup from the headers all the way out the back was in my plans since th beginning but wasn't sure if it was possible and is why I started this thread.....I also e-mailed one of the reps at classicchambered.com and he stated that I might have to have both medium sized pipes run on the right side of the tranny tunnel and that it is definately possible to run such a setup on this type of car! So now my hopes are way up! Thanks again for the advice MB! :Cool:

The_Phoenix

iTrader: (3)

Hey hows it goin? I was going to do this particular exhaust setup a while back like some of you remember but if your wondering, an unnoticed oil leak caused my engine to go BOOM ( no oil) so I had no choice but to get it rebuilt. Fortunately, thats out of the way and now I can get this setup underway. Back when I started this thread, I was shooting for insane HP numbers (700+) but found out that: #1 its not streetable and #2 those are numbers that a drag or strip car would have and my GTA sure as hell aint gonna be a drag car so I'm now shooting for 400+ HP! Ok , I just got my L98 rebuilt and my current exhaust consists of: Hedman shorty headers, I and y-pipe, stock cat and flowmaster 80 series crossflow muffler with 2.5 inch outlets. My new exhaust system will consist of but not limited to: Hooker Super comp 2210-1 LT Headers; (these don't come with the A.I.R. injection tubes but my car does have them so will running these headers cause a problem?), mandrel bent x-pipe done at the shop, a pair of hi-flow cats, and a pair of GMMG chambered pipes which I would like to exit out in front of the rear wheels hopefully through the ground fx using rectangular muffler tips of course!. If I change my mind about this setup (which is less than likely), I'll just stick with a GMMG system. What do you guys think about the setup?

Thanks,

L8R

deepstage69

iTrader: (2)

Here are a couple of vids of mine, dual 3" Powersticks from classicchambered.com

http://videos.streetfire.net/video/9...ers_139148.htm

http://videos.streetfire.net/video/9...T56_145354.htm

The_Phoenix

iTrader: (3)

Damn!! that thing sounds like a monster! Is your setup straight-through or crossflow?

Thanks

deepstage69

iTrader: (2)

They are dual 3 inch, dumped at the rear axle.

19doug90

Why would it hurt your performance? That comes down to the basics of how an engine works.

on the exhaust stroke you have high pressure in the engine, getting sucked out of the engine by the lower atmospheric pressure.

If you go to too big of an exhaust tube the pressure difference between atmospheric and the engine equalizes too quickly and all of that force pulling the burnt gasses out of your engine is lost.

You want to run the absolute smallest exhaust you can without having any backpressure at all. Too small you get turbulence. So its a bit of a fine line

That being said for anything less then 400 wheel hp 2.5" for a dual setup is generally the biggest you need. Sure you "Plan" on the car making 700 hp, but is that next season, or by the time youre 40. Build the system for the engine thats going in for best results.

the chambered mufflers at www.stainlessworks.net sound absolutly unreal, best sounding mufflers ever imo, loud as hell too.

Try to run a crossover tube somewhere (not easy to do) and close to the engine the better.

If youre running axel dumps then it doesnt matter. If you want to run duals out the back youll need an upper panhard relocation bar. Its bent in a different shape and gives you clearance to run the tube over the drivers side.
Both BMR and UMI make them.

hope that helps.

The_Phoenix

iTrader: (3)

I'm actually going for more realistic numbers now because 700hp is wayyy too much for the street. I am shooting for 400-450hp so 3 inch would be the way to go right? I would really like to install an x-pipe on my car too. With that upper panhard relocation bar you mentioned, your saying I can run straight-through true duals out the back? or possibly exiting in front of the rear wheels through the gfx?

Right on! does dumping it at the rear axle make it a bit louder? Right now my car has a flowmaster 80 series muffler and was thinking about cutting off the pipes at the rear axle just to hide those ugly a** downward pointing pipes!

Thanks.
Ruben

19doug90

i was talking rear wheel hp, youre talking flywheel hp. You wont make much more then 300 to the wheels, and dual 3" is completly overkill, your motor will have waay more torque and midrange with a dual 2.5", thats 5" of pipe man.p

While an x-pipe would be fine and dandy good luck finding space for it, if you do manage put up pics because everyone will want to see them. Thats cause it wont happen.

http://umiperformance.com/2024?category_id=136

that little kink in the bar gives you enough room to run a pipe over the drivers side of the axel where there normally wouldnt be enough room. Have more then enough room to run dual 2.5" all the way out the back and over the axel

The_Phoenix

iTrader: (3)

So with my current engine an L98, I can't make 400 to the wheels?? I heard about guys making that much and more with the right mods of course. As for the x-pipe, I'm going to have one custom made at a local exhaust shop similar to this one. Check this thread out: http://members.optushome.com.au/iroc...st/exhaust.htm; it was done on an iroc but should also be able to fit into a GTA. I know it sounds like overkill and it night not be possible but I would like to have it exit in out the front of the rear wheels on each side thru the body gfx somehow or straight through out the back if thats not gonna happen. Thanks for the link bro I think I'll be purchasing one of these soon .

L8R!

19doug90

that part gives you no performance gains just more access to routing piping out the back

notice how that X pipe was run on shortie headers? with those you can curve right by the bellhousing and keep it on one side. With long tubes that crossover pipe has to be run after the transmission, which is fine but with the tubing all on one side you might as well just run a Y pipe.

And if you run a DS safety loop which youll need to run at the strip youre corossover gets pushed that much farther back.

And no your l98 wont make 400 wheel hp. My engine with a stealth ram, slightly better then stock heads and a good sized cam (224/230 duration) with a tko-600 manual transmission so minimal parasitic loss is only good for around 300-310 hp.

400 wheel is pretty much the top end limit with the best combo of parts (afr heads, big cam) for a N/A 355 while still being streetable.