exhaust layout on an 04

**brettmc** · 01-29-2008, 07:04 AM

What is the exhaust configuration on an 04 gto a4? I'd like to know pipe diameter and the locations of resonator(s), cat(s), muffler(s). TIA!

Brett

**Sarge** · 01-29-2008, 07:05 AM

Sure....I have a diagram somewhere on here...I'll find it and post it up for you man...give me a minute or two.

**Sarge** · 01-29-2008, 07:12 AM

OK...here is the guy that invented the hoola hoop squatting in front of a stock 04 GTO exhaust system. There it all is...resonators/cats/mufflers

**brettmc** · 01-29-2008, 07:26 AM

Perfect! Thanks for the pic. Is this a 2.5" system? Glad to see it has an h-pipe.

This system is way too quiet. I want to louden it up and decrease backpressure. I think this would be best accomplished by dumping the resonators and getting new mufflers. Would this affect the O2 sensors? I know you guys will mention a catback but that's not in the budget right now. I'd rather wait and get headers and a headerback system when funds allow.

Does anyone make a direct replacement performance muffler? I looked at summit and jegs and dynomax.com but turned up nothing. If nothing else maybe I can match one up pretty close using the stock muffler measurements.

What says the forum?

Brett

**Sarge** · 01-29-2008, 07:34 AM

I like the loudmouth mufflers...gut the cats/eliminate the resonators....tune out the 02's and haul ass

**brettmc** · 01-29-2008, 07:53 AM

Aren't the loudmouths a glasspack type muffler? I had some dynomax bullets on the vette at one time but started to notice my ears ringing after riding in it. I don't want to get there with the gto.

**Sarge** · 01-29-2008, 08:03 AM

No.

**Rob** · 01-29-2008, 08:55 AM

Its a 2.25" that necks down to 2" in some spots.

**brettmc** · 01-29-2008, 04:17 PM

I checked the slp website and the only reference to gto exhaust listed a loudmouth and loudmouth 2, both straight-thru glasspack-type mufflers...

**brettmc** · 01-29-2008, 04:18 PM

what is CAI?

**Mich's04** · 01-29-2008, 04:50 PM

Originally Posted by brettmc

what is CAI?

Cold Air Induction.

**Sarge** · 01-30-2008, 03:33 AM

Originally Posted by brettmc

I checked the slp website and the only reference to gto exhaust listed a loudmouth and loudmouth 2, both straight-thru glasspack-type mufflers...

Well I have seen a LMII tore in half and there isn't any fiberglass in em that I could see. Mine have been on for a couple of years and have not "changed" tone nor loudness indicative of a glasspack "eating" the glass stuff....so I don't know what in the hell they are talking about frankly.