PURPLEPASSION

Hello. Would like to get opinions on which exhaust from muffler back is best for 04 GTO performance and SOUND!! Sound being important as they seem to purr instead of growel. Understand headers are important, but don't want to deal with that right now. Only significant mod so far is K&N CAI.

Also, what ya think about SportDiablo v. Hypertech? Hypertech has not made one yet for the GTO, but will by winter. Wait or just get Sportdiablo?

Thanks!!

00T\A

You might get better responces in the GTO section or the external section.

PURPLEPASSION

Any opinions as to which exhaust is better for 04 GTO muffler and pipes? Did K&N CAI so far as mod for first step. After exhaust deciding between Hypertech and SportDiablo tuner? Called Hypertech and it comes out beginning of 06. Wait or buy diablo? Any opinions? Not looking to drag, just want to make sure that whatever pulls up beside the goat we can handle.

02 Tahoe on 20s

Previous hypertech owner here. I don't recommend it. I haven't used the Diablosport tuner yet, but its far more robust as far as handhelds go. I have a friend with a modded '04 cobra that absolutely loves his. Good luck

Ben

Crisisman

iTrader: (1)

Which exhaust is better? That depends on what you want.

Every cat-back will give you a different sound, so if going for a certain sound I'd search for clips and go with what appeals most.

Many cat-back makers offer a variety of tips as well. Do you want to use your stock bumper, or are you willing to modify? Again, this is what appeals to you.

If performance is what you want, then it's a matter of airflow and tuning. The Stainless Works system is the only dual 3" system, but their quality control SUCKS. I had to cut two different pieces to get mine to fit, plus the fitting of the various pieces was so loose, even after clamping, that I welded the sections together. Magnaflow has a 2 3/4" dual system that, given Magna's reputation, will probably fit right the first time. Corsa also has a 3" system, but it uses a Y pipe to put all the airflow through a single exhaust, so it's not as much total airflow as the SW or MF systems. Then there are a number of systems with dual 2 1/2". Take your pick.

2edybrd

Like everyone says, what do you want? GMMG has a chambered catback. SLP has two types of catback, one with NO mufflers and one with Race mufflers. Corsa has a catback that will reduce your dual exhaust into a single exhaust.


Or you get a Magnaflow x-pipe and replacement mufflers that will give cat back numbers and still be "relatively" quiet. The dual exhaust already flows really well, so match it up with longtubes and you're set, And you just saved around 3- 400 bucks.

GTO_Scott

iTrader: (3)

Not sure if I'd agree with you. The Corsa system flows extremely well, it gives you more room under the car to work around (driveshaft, rearend, etc) and reduces weight. There are several people that run it on 400-500rwhp GTOs.

For me, the Corsa Touring was too loud with LT headers, even with performance cats, and I wanted to go to the 05 bumper.

You really aren't going to gain much from a catback unless you are doing heads, camshaft, etc. It's more for sound than performance. There are a lot of people out there with a lot more power than a stock 04 or 05 GTO. If you want to give those people a good run, you'll want to look at Nitros, forced induction, or a well thought out head/cam package.

Betwen SLP, Corsa, SW, Flowmaster, Borla, Magnaflow, etc you aren't going to see much difference in performance (sound is a different subject) on a mainly stock GTO.

Also, be aware that a cold air induction system can actually cause a performance decrease if it increases the amount of underhood heat and your IAT sensor retards your advance because of the 98F+ temps. This can be mitigated with IAT table adjustments and IAT sensor reloation (like the LPE system).

platinum

I Make 500 Rwhp On My V And I Use B&b And It Sounds Good. I Am Doing The Heads And Cam Now Also So I Hope To Make Over 600 To The Wheels In The V

PURPLEPASSION

Maybe was a little too vague(LOL). Have seriously considered going to '05 rear fascia. Looking for more of the muscle growel and more open than stock muffler and pipes for better performance being as there will be more mods to follow, street appearance would be next in line. Was told the exhaust is a good second mod, so was going from there. Almost bought the slp loudmouth yestereday, but thought would see what others have tried or thought before investing time and money.

One of the guys(mustang owner) has the flowmaster 40(no delta flow)and says it gives him great sound(which it does) and has been an excellent change for him. But then started researching and it seems that is not a good system for the GTO for some reason? It is a cheaper system which also raised some red flags as I believe you get what you pay for in most cases. Nobody around here is familiar with GTO's, mostly stang. So, hoping this board could give some good ideas.

Sorry to hear the hypertech did not work well for the mustang. Will check more into the diablo tuner, but was not happy with the reading I've done so far on it in comparison with the hypertech. But this is the first time recieving any response on that issue, thanks for the input. Nobody has much to say on that one as most haven't tried both to see which is better.

LOVE THE YELLOW JACKET!!!

GTO_Scott

iTrader: (3)

I would recommend you also include a dedicated 04+ GTO website for your info. http://www.ls1gto.com

gametech

iTrader: (1)

My sts exhaust seemed to add quite a bit of power. Sorry, I just couldn't help saying that.

Tom@SpeedInc

iTrader: (5)

I put a 05 rear bumper on my 04 then put on a stainless works 3" cat back, its really nice, very mellow sounding with SW turbo mufflers. IIRC SW is the only company that makes a 3" piped GTO catback.

oct03gto

iTrader: (15)

I put a corsa cat back with 4" tip on my 04'. With out headers, the sound is verry apealing. I will find out how bad the back pressure will be with stainless work headers and converter deletes. I think that the anyone listening to this cat back system in traffic, will definatly be able to tell wich car it is coming from. The only problem with the exaust is the interior resonance. I find it hard to tune the radio just right when on the road. But who buys these cars for the radio?

2002firebirdguy

From the clips I've heard I'm so far going with the stainless works chambered cat back and long tube headers with cats. I am trying to go with the more muscle car sounding sound as well. Stainless is as close as I've found so far.

WAHUSKER

iTrader: (4)

I have looked at & listened to the Borla cat back the PFYC -------------->
sells. Nice looking & sounding kit, and fairly priced IMO. But I have no idea what the HP #s are for it.

PURPLEPASSION

Well, guess I f'd this one good. Talked to all the older "car club" members that had excellent sounding exhaust and they all had flowmaster 40 series. Told the garage that was what I wanted. The mechanic ordered the "American Thunder Series" which he said had the series 40. NOT! It has the super 40. More horsepower supposedly(?), but no where near the sound the older timers are getting. So, here I sit with my mousy exhaust after expending hundreds of dollars. Guess I should have stuck with stock?!?!

2002firebirdguy

Sucks to hear that man. I just put the Corsa sport on my bone stock goat and it sounds gooooooooooooood! Can't wait to install my headers.

Rob

PURPLEPASSION

Rob. . . I was gonna go with the slp LM, but changed my mind at the last minute. Going back tomorrow and hopefully the guy will remember me stating 40 series not super 40. But what's the chance he'll admit he ordered the wrong part. The two sound totally different on the car. But then this one does have better dyno stats from flowmaster, rpm. Sound or slightly better performance? What do you think? It sounds almost stock right now unless you stomp it then it opens a little. I also put the CAI on it tonight. But glad to hear you're happy with yours. Much enjoyment to ya!

2002firebirdguy

Yeah I'm sure he won't admit he ordered the wrong part. I mean it's an honest mistake but you should get what you pay for. From what I've heard I really don't care for the flowmaster on our cars but if you like it more power to ya! Everyone likes something different! That's what makes the world go round. Glad you're happy with it!

GTO_Scott

iTrader: (3)

Which one did you end up getting?