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How does the GMMG flow?

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Old Feb 1, 2011 | 10:43 PM
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Default How does the GMMG flow?

So like the title says, how does this system flow compared to the Loudmouth systems?? It would seem like the pipe that comes from the I-Pipe after the axle and goes to the driverside, then back to muffler and out the passenger side would hurt performance....or no?

Thinking of getting the GMMG, really love how it sounds but just thought i would ask about this.
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Old Feb 2, 2011 | 02:38 PM
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The loudmouth is the best flowing exhaust produced if you want to go out the back. There's nothing in it. The gmmg, imo, is the best sounding and is pretty free flowing. Its not going to hurt you if that's what your worried about.
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Old Feb 2, 2011 | 04:36 PM
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Originally Posted by 94Z28-MSTGKLR
The loudmouth is the best flowing exhaust produced if you want to go out the back. There's nothing in it. The gmmg, imo, is the best sounding and is pretty free flowing. Its not going to hurt you if that's what your worried about.
I would have to say the SLP 2OTL is right up there with being the best free flowing exhaust as well. Even for being a cat-back, they flow extremely well and sound great. But, the GMMG sounds even better, thus the reason I too am looking at getting a GMMG, its butta!
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Old Feb 2, 2011 | 04:56 PM
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If your going to spend that kind of money, why not do custom true duals. My custom duals cost me $500 at my local shop all I supplied were the mufflers. $500 got me custom piping and bends, an X pipe, AND 2 3" chrome slash tips. $500 included labor!!
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Old Feb 2, 2011 | 05:21 PM
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wait for a deal on GMMG's. . . . I cannot believe how lucky i got, traded my SLP lm1 that where on the car when i boguht it and 200$ cash for the GMMG's. If i could do it again i would have spent more and waited longer for them
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Old Feb 2, 2011 | 07:27 PM
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Originally Posted by PheonixLS1
If your going to spend that kind of money, why not do custom true duals. My custom duals cost me $500 at my local shop all I supplied were the mufflers. $500 got me custom piping and bends, an X pipe, AND 2 3" chrome slash tips. $500 included labor!!
Are those custom duals out the back or dumped? Ive thought about it but idk, there's only 1 guy here locally who can do a good custom exhaust system but he doesnt have a bender. He just cuts up the pipe and pieces them together. He doesnt charge alot though, the other guys dont really know wtf there doing lol
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Old Feb 2, 2011 | 08:02 PM
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I cant imagine those chambered mufflers are too restrictive...you could throw a golf ball through them and not hit anything...just the little tabs on the walls, other than that it's a straight through muffler.

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Old Feb 2, 2011 | 08:19 PM
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^ That's a powerstick. I ran those on a set of duals I had. Great mufflers and if you like the gmmg sound they are perfect for a dual setup. The gmmg muffler is almost identicle to a powerstick. I think the only difference is the number of crimps on the case
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Old Feb 2, 2011 | 08:27 PM
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Originally Posted by PheonixLS1
If your going to spend that kind of money, why not do custom true duals. My custom duals cost me $500 at my local shop all I supplied were the mufflers. $500 got me custom piping and bends, an X pipe, AND 2 3" chrome slash tips. $500 included labor!!
Because its a quality piece, it bolts right up, sounds amazing, its stainless steel, and there's no ground clearance issues with it. Duals are great, don't get me wrong, I've run both duals and a gmmg in the past. Duals are generally made from aluminuzed steel, and with them, must people run stainless mufflers and after 3-4 years the pipess are rusted up. 3-4 years from now the gmmg I just ordered yesterday will still look as good as the day I bolt it up. Other than that, there is no reason to run a gmmg over duals.
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Old Feb 2, 2011 | 08:53 PM
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They flow great. I took my GMMG off for td's and couldn't feel any difference. Now I have a LM1and still can't feel a difference. I'm putting a dual/dual on soon to go into sleeper mode lol.
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Old Feb 2, 2011 | 11:30 PM
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Originally Posted by 94Z28-MSTGKLR
^ That's a powerstick. I ran those on a set of duals I had. Great mufflers and if you like the gmmg sound they are perfect for a dual setup. The gmmg muffler is almost identicle to a powerstick. I think the only difference is the number of crimps on the case
I know it's a powerstick, I run them on my car GMMG looks nearly identical inside and out other than it is stainless steel. Just put that up as a demonstration of what the insides look like on a chambered stick muffler.
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Old Feb 3, 2011 | 07:14 AM
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Originally Posted by MasterTomos
I know it's a powerstick, I run them on my car GMMG looks nearly identical inside and out other than it is stainless steel. Just put that up as a demonstration of what the insides look like on a chambered stick muffler.
I know you know, I was just making it clear to the op because you didn't mention it. That's all.
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Old Feb 3, 2011 | 07:25 AM
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Originally Posted by MyFirstLS1
wait for a deal on GMMG's. . . . I cannot believe how lucky i got, traded my SLP lm1 that where on the car when i boguht it and 200$ cash for the GMMG's. If i could do it again i would have spent more and waited longer for them
Dude what are you trying to say here? Been doing some ??
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Old Feb 3, 2011 | 09:59 AM
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HAHA, I had to read that a few times to try and figure out what he was saying, and I'm still not sure
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Old Feb 3, 2011 | 06:48 PM
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Thanks for all the info guys, i just kinda thought that the piece of pipe where it comes down over the axle, across the driverside then turns back into the muffler back to the passengerside then straight out back may hurt performance a bit but if it doesnt. Then that's great, but i think im already set on going after this exhaust. Kooks Duals would be sweet, but cant see myself dropping that much cash on it.
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Old Feb 6, 2011 | 07:00 PM
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Originally Posted by Badguy7
Are those custom duals out the back or dumped? Ive thought about it but idk, there's only 1 guy here locally who can do a good custom exhaust system but he doesnt have a bender. He just cuts up the pipe and pieces them together. He doesnt charge alot though, the other guys dont really know wtf there doing lol
Custom out the back.
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Old Feb 6, 2011 | 10:02 PM
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GMMG flows fine. Sounds great too. I swapped the slp dual dual from my camaro for the GMMG and the Car felt exactly the same power wise.

The sound was just amplified about 50%
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Old Feb 8, 2011 | 12:22 AM
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Flows great for a catback. However i ditched mine for TDs and im glad i did, tons more midrange
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