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Magnaflow to Gmmg

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Old Jul 15, 2007 | 05:51 PM
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Default Magnaflow to Gmmg

I'm switching to Gmmg, I am currently running lt's and ory w/magnaflow, is the GMMG system I-pipe 3" or will I need to adapt? checked their site w/no luck.

let me know please, thanks
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Old Jul 15, 2007 | 05:53 PM
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i had a buddy that had gmmg and went TO magnaflow and gained like 15rwhp because the gmmg was restrictive
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Old Jul 15, 2007 | 06:00 PM
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thats nice. but that wasn't my question
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Old Jul 15, 2007 | 06:07 PM
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i went from magnaflow to gmmg on my car. it bolted right up. however, i felt the car was a little slower with the gmmg as well....
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Old Jul 15, 2007 | 06:18 PM
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Originally Posted by TUFAS4U
thats nice. but that wasn't my question
i was just trying to fore-warn you that you'll probably loose power but i do beleave its a 3 inch i pipe
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Old Jul 15, 2007 | 06:50 PM
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thanks
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Old Jul 15, 2007 | 06:50 PM
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loss of low end power/torque mainly I suspect
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Old Jul 15, 2007 | 07:13 PM
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well my buddy had a 6-speed 01 ss with longtubes and GMMG and i had a 98 auto Z28 with longtubes and true duals and when he had the gmmg i beat him pretty bad on the highway but when he switched to the magnaflow he slaughtered me
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Old Jul 15, 2007 | 07:21 PM
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GMMG has no muffler, so as a matter of physics, there is little to no restriction at all. Does the Magnaflow system use a muffler? Or resonator? If it uses a muffler I will guarantee you there is more restriction than the GMMG system. If it uses a resonator or some sort of chamber, then it's probably a wash between the two. You can't really get less restrictive than no muffler at all.
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Old Jul 15, 2007 | 07:22 PM
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I have NEVER read anything bad about the GMMG system besides the high price tag, and how are you goin to loose power when its just straight pipes? If anything your goin to loose weight b/c of no muffler. And to answer your question yes its 3 inch over the axle then it splits into 2.5 inches in the tailpipes I believe so it should bolt right up.
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Old Jul 15, 2007 | 07:22 PM
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i don't understand how a magnaflow can outperform a GMMG. the GMMG should be far less restrictive. even oxidizr said the magnaflow isn't good for over 400 rwhp without being restrictive

^^^ sounds like your buddy learned to drive a little better the second race.
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Old Jul 15, 2007 | 08:07 PM
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i don't know what you guys call those but they look like mufflers to me http://gmmginc.net/Exhaust/

magnaflows arent chambered, gmmg is, magnaflow is straight through

but idk i could be wrong i was just trying to help out
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Old Jul 15, 2007 | 08:19 PM
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GMMG is a straight thru design. From this pic i'm almost certain the magnaflow is a chamber style.



Originally Posted by darkside98
i had a buddy that had gmmg and went TO magnaflow and gained like 15rwhp because the gmmg was restrictive
I'm sure there was other mods to the car. There's no way he'd gain 15hp by installing magnaflow over gmmg.
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Old Jul 15, 2007 | 08:23 PM
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Originally Posted by TUFAS4U
I'm switching to Gmmg, I am currently running lt's and ory w/magnaflow, is the GMMG system I-pipe 3" or will I need to adapt? checked their site w/no luck.

let me know please, thanks
And to the original question. The GMMG should bolt right up, unless you had any custom work done.
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Old Jul 15, 2007 | 08:24 PM
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Originally Posted by darkside98
i don't know what you guys call those but they look like mufflers to me http://gmmginc.net/Exhaust/

magnaflows arent chambered, gmmg is, magnaflow is straight through

but idk i could be wrong i was just trying to help out
Those are called "chambers" because they do not interrupt the flow of exhaust by diverting it. They simply affect soundwaves. (most) Mufflers divert the flow of exhaust, and restrict flow in the process.
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Old Jul 15, 2007 | 08:35 PM
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Darkside, I think you should of just stepped out of this one. GMMG is nothing more then stainless steel resonators. Straight through design, they look nothing like mufflers.
My GMMG bolted right up to my 3" ypipe with no problems at all. But I have to warn you it will rasp around 2200-2700 rpms with an ORY.

Travis
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Old Jul 15, 2007 | 10:10 PM
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Default Magnaflow

Originally Posted by BLK02TA
GMMG is a straight thru design. From this pic i'm almost certain the magnaflow is a chamber style.





I'm sure there was other mods to the car. There's no way he'd gain 15hp by installing magnaflow over gmmg.

My magnaflow muffler doesn't look like the one pictured but I did go from a 13.8 at 99.8 MPH to 13.20 at 105 MPH after replacing the stock muffler with it .
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Old Jul 15, 2007 | 10:18 PM
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Originally Posted by Thebeast431
Darkside, I think you should of just stepped out of this one. GMMG is nothing more then stainless steel resonators. Straight through design, they look nothing like mufflers.
My GMMG bolted right up to my 3" ypipe with no problems at all. But I have to warn you it will rasp around 2200-2700 rpms with an ORY.

Travis
any sound clips beast?
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Old Jul 15, 2007 | 10:24 PM
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Originally Posted by Thebeast431
Darkside, I think you should of just stepped out of this one. GMMG is nothing more then stainless steel resonators. Straight through design, they look nothing like mufflers.
My GMMG bolted right up to my 3" ypipe with no problems at all. But I have to warn you it will rasp around 2200-2700 rpms with an ORY.

Travis
yeah your right i shouldn't have said anything, sorry for just telling you what my friend expierenced with the swap, good luck with your GMMG
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Old Jul 15, 2007 | 10:53 PM
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sorry if I started a pissing match guys.
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