GMMG installed...Impressions.
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From: Land of the FOID
GMMG installed...Impressions. Well after waiting a month I finally got the infamous GMMG system in the mail yesterday. Let me just start by saying that all the hype surrounding this system is absolutely TRUE! It's everything I hoped it was going to be.
When I took the stock cat-back off and started up the car I was a little nervous because I really liked the sound of the open headers through high-flow cats. I was doubtful that it could sound as good or better than what I had just heard. Slightly reluctant I pressed forward and got the system installed. When I started it up I had a huge grin on my face. It's loud, but in a very refined way that the open headers didn't provide. It kind of reminds me of a jet engine or something. The nice thing is when at low RPM's it's pretty quiet so you don't get annoyed or have to talk loud while cruising. I made a list of Pros and Cons below.
PROS
- Can't beat the amazing sound
- High quality craftsmanship
- Excellent instructions (in color!)
- Optional tips really fill the space well for T/A's
CONS
- Actually heavier than stock (this disappointed me, but it's only 2lbs)
- Optional tips are great, but for the money the ends should be rolled
- Real PITA to get the tips level. Tried for 2 hrs but one is still 1/4" higher.
- Didn't like cutting the stocker. Heard you may not if you have a lift.
- $$$$$$$
When I took the stock cat-back off and started up the car I was a little nervous because I really liked the sound of the open headers through high-flow cats. I was doubtful that it could sound as good or better than what I had just heard. Slightly reluctant I pressed forward and got the system installed. When I started it up I had a huge grin on my face. It's loud, but in a very refined way that the open headers didn't provide. It kind of reminds me of a jet engine or something. The nice thing is when at low RPM's it's pretty quiet so you don't get annoyed or have to talk loud while cruising. I made a list of Pros and Cons below.
PROS
- Can't beat the amazing sound
- High quality craftsmanship
- Excellent instructions (in color!)
- Optional tips really fill the space well for T/A's
CONS
- Actually heavier than stock (this disappointed me, but it's only 2lbs)
- Optional tips are great, but for the money the ends should be rolled
- Real PITA to get the tips level. Tried for 2 hrs but one is still 1/4" higher.
- Didn't like cutting the stocker. Heard you may not if you have a lift.
- $$$$$$$
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From: The South
The GMMG is, IMO, the best sounding cat-back. If I were to ever, for some reason, run a Y-pipe on an LS1 with headers it would probably be with the GMMG.
Edit: The tips just work that way. I could never get them level on my LM either.
Edit: The tips just work that way. I could never get them level on my LM either.
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From: Hometown:Mount Carmel, IL Current: Las Vegas, NV
here's an idea i've had. Probably crazy but something ive thought of over the weekend. How wide is the area the Y pipe is running through? could you run dual 2.5 inch pipes through that? and if so, before the cats, put in a balance tube and cut off the actual "y" of the y pipe. and run duals back to the GMMG and where it Y's out into the two chambers, cut that off and run each 2.5 inch pipe into an individual chamber? call me crazy, but just a theory, would it work?
Originally Posted by f-bodman
I don't know about your blueprinting skills but the idea, in theory, is awesome. Now we just need somebody to try it. 
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From: Hometown:Mount Carmel, IL Current: Las Vegas, NV
awesome. i gotta get my car on a lift and ill check it out. then i gotta get some ***** to as you said hack the 800 dollar exhaust. plus pipe for the duals.
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Originally Posted by Swang
awesome. i gotta get my car on a lift and ill check it out. then i gotta get some ***** to as you said hack the 800 dollar exhaust. plus pipe for the duals.
Originally Posted by cyphur_traq
here, check this out.
(click on the photo for website)
that would be an interesting system.
(click on the photo for website)
that would be an interesting system.
but you posted wht i described..lol
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From: rosemount,mn/windsor locks,ct
Originally Posted by cyphur_traq
here, check this out.
(click on the photo for website)
that would be an interesting system.
(click on the photo for website)
that would be an interesting system.
most duals out the back run about a grand. i think the guy that had that setup(and sold it, he's a member on this forum) said it cost him 1200. i'm sure any GOOD exhaust shop familiar w/f-bodies could do it for less. i know lanes would charge about a grand, i've had him qoute me.
Originally Posted by 02 Camaro SS
that exhaust looks sick. how would that driver side pipe clear the panhard rod?
:edit: nevermind, Panhard Rod Relocation Kit
:edit: nevermind, Panhard Rod Relocation Kit
