GMMG or duals?
GMMG or duals? Maybe you guys could help me decide what exhaust I should go with based on my needs / money.
I currently have a Borla with LT headers and an ORY and it's a little too raspy for me. I want a really great sounding exhaust, not looking for the slight hp gains over one or the other.
So here goes my question. If I were to get duals, I would be going with catted duals, under the axle out the back. If I went GMMG I would be going with a catted y pipe. What would be the differences in price assuming I got a used gmmg / y pipe compared to purchasing tips, mufflers + cats and having a shop fab me a dual exhaust out back? Also would I still get the great sound that everyone raves about with their dumped duals?
Or would it be better to buy something like the TSP duals and then have the shop weld in the cats + extend it?
I currently have a Borla with LT headers and an ORY and it's a little too raspy for me. I want a really great sounding exhaust, not looking for the slight hp gains over one or the other.
So here goes my question. If I were to get duals, I would be going with catted duals, under the axle out the back. If I went GMMG I would be going with a catted y pipe. What would be the differences in price assuming I got a used gmmg / y pipe compared to purchasing tips, mufflers + cats and having a shop fab me a dual exhaust out back? Also would I still get the great sound that everyone raves about with their dumped duals?
Or would it be better to buy something like the TSP duals and then have the shop weld in the cats + extend it?
I ran duals dumped with bullets and it was just too loud for me w/o cats, I always liked the sound of GMMG with cats. I did the TSP dual pkg and I know they offer different muffler choices now. I ended up going with the Hooker, lt's and no cats and was happy with the sound.
If you have no taste for rasp, I would steer clear of the GMMG as well. I have never been very fond of that catback even with cats. 
Duals done RIGHT will put a serious smile on your face, no doubt. Some people are in love with the way GMMG's sound, but not everyone.
Duals done RIGHT will put a serious smile on your face, no doubt. Some people are in love with the way GMMG's sound, but not everyone.
People will tell you that duals are loud, which many are, but they can be kept quiet. If I follow through with the plan for mine, I'll be running Magnaflow 4x9 mufflers and taking the pipes out the back. This should keep it a bit quieter.
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why are you againt no cats? if its for smog you can either jsut run test pipes inplace or just take an afternoon and bolt up your old exhaust, but im guessing if you have LTs now emissions isnt an issue... duals will deffinatly sound better, and all the way out wouldnt bother you at all... all the GMMGs ive heard rasp like hell to man so be careful
duals
gmmg is comparable to glass packs aka raspy as all get out.
i have the aforementioned 4x9 magnaflows dumped at the axle, they sound excellent. full 3" system with x pipe. very little interior drone, car is docile cruising and accelerating, but WFO makes the sky fall.
gmmg is comparable to glass packs aka raspy as all get out.
i have the aforementioned 4x9 magnaflows dumped at the axle, they sound excellent. full 3" system with x pipe. very little interior drone, car is docile cruising and accelerating, but WFO makes the sky fall.
well for two reasons. One is I dont want getting stopped by a (%# cop, and getting a huge, fine, or getting my car towed / impounded for a stupid reason like no cats, which they could do. The other reason is that most shops wont fab up a system for me without cats, so I'll have to have them in order for the shop to touch the exhaust.
Originally Posted by orangeapeel
I have just had them for soooooo long. Plus STS wont work with duals. 
& 
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From: I-L-L-I-N-O-I-S
Guys, some of you need to get your facts straight about the GMMG...It absolutely does NOT rasp at all with highflow cats on the car...It's very refined and clean sounding. You must have heard them without cats...
Now if you're running an ORY (no cats), then correct, the GMMG will sound very raspy. But then again, what cat-back system (SLP dual/dual excluded) doesn't sound like raspy-A$$ without cats on an LS1. 
BTW, check out my thread on this page about the 8 sound clips I just put up last night of my car with the GMMG/Kooks LT's (catted-Y). I know sound preference is strictly a matter of opinion, but I'd take that set-up over any other true dual one except for the Flowmaster 1-chambers dumped (which I'm having installed next week).
I just happen to like the Flowmaster true duals a little more...
Mike
Now if you're running an ORY (no cats), then correct, the GMMG will sound very raspy.
But then again, what cat-back system (SLP dual/dual excluded) doesn't sound like raspy-A$$ without cats on an LS1. BTW, check out my thread on this page about the 8 sound clips I just put up last night of my car with the GMMG/Kooks LT's (catted-Y). I know sound preference is strictly a matter of opinion, but I'd take that set-up over any other true dual one except for the Flowmaster 1-chambers dumped (which I'm having installed next week).
I just happen to like the Flowmaster true duals a little more...Mike
Originally Posted by 2000LS1Z28
Guys, some of you need to get your facts straight about the GMMG...It absolutely does NOT rasp at all with highflow cats on the car...It's very refined and clean sounding. You must have heard them without cats...
Now if you're running an ORY (no cats), then correct, the GMMG will sound very raspy. But then again, what cat-back system (SLP dual/dual excluded) doesn't sound like raspy-A$$ without cats on an LS1.
BTW, check out my thread on this page about the 8 sound clips I just put up last night of my car with the GMMG/Kooks LT's (catted-Y). I know sound preference is strictly a matter of opinion, but I'd take that set-up over any other true dual one except for the Flowmaster 1-chambers dumped (which I'm having installed next week). I just happen to like the Flowmaster true duals a little more...
Mike
Now if you're running an ORY (no cats), then correct, the GMMG will sound very raspy.
But then again, what cat-back system (SLP dual/dual excluded) doesn't sound like raspy-A$$ without cats on an LS1. BTW, check out my thread on this page about the 8 sound clips I just put up last night of my car with the GMMG/Kooks LT's (catted-Y). I know sound preference is strictly a matter of opinion, but I'd take that set-up over any other true dual one except for the Flowmaster 1-chambers dumped (which I'm having installed next week).
I just happen to like the Flowmaster true duals a little more...Mike