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Gmmg vs. Slp LM

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Old Oct 6, 2009 | 12:30 AM
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Default Gmmg vs. Slp LM

Ive got long tubes, catted y and slp lm1(with cam). Im on the fence about picking up a GMMG catback. I cant remember what it sounds like, also videos online dont do much justice for loud cars with lt headers. So my question is how much quieter or louder is the gmmg going to be? I like the way it idles and wide open but it has some parts of the throttle that just dont sound that good. Opinons on sound difference between the two would help. Thanks.
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Old Oct 6, 2009 | 12:35 AM
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They sounded the same to me honestly, the GMMG reminds me a bit more of classic muscle. I LOVE the LM 1 though, It lets people know it's a V8, and at WOT it sounds like the universe is going to tear to pieces. My other favorite is the Borla XR-1, have you looked into that?
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Old Oct 6, 2009 | 04:30 PM
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I definitely loved my LM1 when WOT. The raspy sound is what I couldnt deal with anymore.
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Old Oct 6, 2009 | 05:03 PM
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I liked it for a while but couldn't take it any longer
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Old Oct 6, 2009 | 05:16 PM
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i wish to know the difference also i need something quieter than my loudmouth its way to fkn loud and i would personally drive with open headers.
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Old Oct 6, 2009 | 05:48 PM
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Love mine, but im also catted w/ Mids
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Old Oct 6, 2009 | 05:49 PM
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Originally Posted by KRAZY K 2000 TA
i wish to know the difference also i need something quieter than my loudmouth its way to fkn loud and i would personally drive with open headers.
I can't tell you the difference between the lm and gmmg but if you want to do something to your lm you can throw a borla xr1 muffler on it or do the powerflo conversion. I have experience with them. If you want to hear my car go to youtube and search "detoxx03"
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Old Oct 6, 2009 | 08:42 PM
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Thanks for the input, i'm not really worried about being too loud, car comes out here and there to rip around. I've heard a lm set up with a borla in it. Still on the fence about switching, might just have to keep the lm and get the oval gmmg tips.
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Old Oct 7, 2009 | 01:03 AM
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ive had a LM1 and GMMG on my car, albeit mine is an LT1. volume wise, they are about the same, GMMG being a little quieter. the drone is what finally made me get a GMMG. you wont regret it.
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Old Oct 7, 2009 | 09:04 AM
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Originally Posted by Jroc99SS
Ive got long tubes, catted y and slp lm1(with cam). Im on the fence about picking up a GMMG catback. I cant remember what it sounds like, also videos online dont do much justice for loud cars with lt headers. So my question is how much quieter or louder is the gmmg going to be? I like the way it idles and wide open but it has some parts of the throttle that just dont sound that good. Opinons on sound difference between the two would help. Thanks.
I've only heard the GMMG in person one time and it was on a stock manifold and Y-pipe car. At the time my car was sporting the LM1 catback with its stock manifolds and Y as well. I would say the GMMG is just barely quieter and a tad more refined sounding.

I now have LT's and a Catted Y matched to my LM, as well. I'm curious what cam you went with and if you have a sound clip or video of your car so I could hear it. If not, thats cool. Good luck with your decision.
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Old Oct 7, 2009 | 10:56 AM
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I had an LM1 for a while, anywhere from stock to mild H/C to slightly more powerful H/C all the way to my 4X setup... at the 4X setup I could not longer take the drone and went to true duals lol

The LM1 is a good exhaust, nice and free flowing, but that damn 2500rpm resinance was terrible lol

car sounds pretty damn good with the true duals, but i can not comment on a GMMG having never heard one in person.
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Old Oct 7, 2009 | 01:34 PM
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Yeah, I've seen hundreds of fbodies, but can't remember the sound of gmmg on a cam or hc set up or even with headers.

I agree, around 2500 it gets all pipey with the lm
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Old Oct 7, 2009 | 01:38 PM
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Originally Posted by Mumbles
I've only heard the GMMG in person one time and it was on a stock manifold and Y-pipe car. At the time my car was sporting the LM1 catback with its stock manifolds and Y as well. I would say the GMMG is just barely quieter and a tad more refined sounding.

I now have LT's and a Catted Y matched to my LM, as well. I'm curious what cam you went with and if you have a sound clip or video of your car so I could hear it. If not, thats cool. Good luck with your decision.
Here's a clip of my lm setup with cats


http://www.youtube.com/watch?v=D1b5z...=youtube_gdata
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Old Oct 7, 2009 | 03:15 PM
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Originally Posted by Jroc99SS
Here's a clip of my lm setup with cats
Thanks Jroc99SS. Car sounds good at idle. You didn't say what cam you're running. (Maybe you'd rather not say. And that's fine too.) I'm hoping to keep my LM when I find a H/C Combo. Right now I'm looking for H/C setups that are matched to LT's/LM, so I can get an idea what some sound like. Thanks for the video, man.
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Old Oct 7, 2009 | 06:59 PM
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Originally Posted by Mumbles
Thanks Jroc99SS. Car sounds good at idle. You didn't say what cam you're running. (Maybe you'd rather not say. And that's fine too.) I'm hoping to keep my LM when I find a H/C Combo. Right now I'm looking for H/C setups that are matched to LT's/LM, so I can get an idea what some sound like. Thanks for the video, man.
Honestly i dont remember the duration or lift at hand (its filed somewhere) but i can tell you its close to texas speed magic stick 3. FWIW.. a quality set of heads such as afrs, and a fast 90 are key to getting the ls1 to make power with a big stick
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Old Oct 8, 2009 | 03:34 PM
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Go with the GMMG, you won't be disappointed. It is an awesome exhaust, fits great, and sounds NASTY. SLP LM sounds like crap with H/C. just my $.02
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Old Oct 8, 2009 | 05:18 PM
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Originally Posted by Mumbles
Thanks Jroc99SS. Car sounds good at idle. You didn't say what cam you're running. (Maybe you'd rather not say. And that's fine too.) I'm hoping to keep my LM when I find a H/C Combo. Right now I'm looking for H/C setups that are matched to LT's/LM, so I can get an idea what some sound like. Thanks for the video, man.
Not to change the topic, but did you ever get a video of your car on the road with the lm and lts? I have the lm1 right now and I'm curious as to how it sounds with lts.
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