GMMG is off - 4" Mufflex is on
#1
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After enjoying a few years with the sweet sounds of a GMMG cat-back and stock exhaust manifolds, the need for more power prompted me to get headers. After they were on the car it was much louder, even with a catted y-pipe. I was ok with it for a while, but a few long trips later it began wear on me. I had to make a change to something quieter, but still maintain the good flow of the GMMG.
Here's what I wanted out of my new exhaust system:
* Flow enough for 700 rwhp with FI
* Must go over the axle
* Want some sound at WOT, but mellow at idle and cruise
* No rasp from 2000-2300, or anywhere else
My options were:
* Bassani 2 1/2 true dual cat-back
* SW 3 1/2 dual exit cat-back
* Mufflex 4 dual exit cat-back
* Mufflex 4 single exit cat-back (w/Magnaflow)
* Custom 3 true dual system
Found this yesterday and reordered it based on power potential: (quoting JRP)
* 2.75 single system - 310hp engine
* 3 single system - 370hp engine
* 2.25 dual system - 457hp engine
* 3.5 single system - 503hp engine
* 2.5 dual system - 513hp engine
* 4 single system - 657hp engine
* 3 dual system - 812hp engine
After much deliberation, I decided to go with the Mufflex 4-inch single exit with Magnaflow muffler. My exhaust guy, Rich in Wylie, TX did an excellent job installing this system along with a Kooks 2x3 into 4 catted y-pipe. Fitment is fairly tight with this system, so finding a muffler shop that will do the extra tweaks to make it hang right is very important.
Mufflex impressions... The dreaded rasp is gone. Its now quieter than the GMMG at idle and cruise, but still has a good bark at WOT. The tonality is overall deeper. Hitting the gas while going under an overpass sounds like a stout muscle car again instead of an old truck with a rusted out muffler. Dont get me wrong, I love the way a GMMG sounds, but just not with headers.
EDIT: Added pics after I got the entire system ceramic coated black. This was done locally and cost about $325. I think it might actually be a little quieter now, but it's hard to tell because the car's been down for 2 weeks.
Here's what I wanted out of my new exhaust system:
* Flow enough for 700 rwhp with FI
* Must go over the axle
* Want some sound at WOT, but mellow at idle and cruise
* No rasp from 2000-2300, or anywhere else
My options were:
* Bassani 2 1/2 true dual cat-back
* SW 3 1/2 dual exit cat-back
* Mufflex 4 dual exit cat-back
* Mufflex 4 single exit cat-back (w/Magnaflow)
* Custom 3 true dual system
Found this yesterday and reordered it based on power potential: (quoting JRP)
* 2.75 single system - 310hp engine
* 3 single system - 370hp engine
* 2.25 dual system - 457hp engine
* 3.5 single system - 503hp engine
* 2.5 dual system - 513hp engine
* 4 single system - 657hp engine
* 3 dual system - 812hp engine
After much deliberation, I decided to go with the Mufflex 4-inch single exit with Magnaflow muffler. My exhaust guy, Rich in Wylie, TX did an excellent job installing this system along with a Kooks 2x3 into 4 catted y-pipe. Fitment is fairly tight with this system, so finding a muffler shop that will do the extra tweaks to make it hang right is very important.
Mufflex impressions... The dreaded rasp is gone. Its now quieter than the GMMG at idle and cruise, but still has a good bark at WOT. The tonality is overall deeper. Hitting the gas while going under an overpass sounds like a stout muscle car again instead of an old truck with a rusted out muffler. Dont get me wrong, I love the way a GMMG sounds, but just not with headers.
EDIT: Added pics after I got the entire system ceramic coated black. This was done locally and cost about $325. I think it might actually be a little quieter now, but it's hard to tell because the car's been down for 2 weeks.
Last edited by white01ss; 06-03-2008 at 09:11 PM. Reason: added pics
#4
TECH Junkie
iTrader: (4)
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i hate the way the gmmg sounds. i feel if you want your vehicle to sound like that, save yourself the money and just take a hammer to some 3" pipe and leave the mufflers off. there is your chambered exhaust. i never understood why someone would want such a beautiful car to sound like my 84 chevy truck with duals and glasspacks.
#7
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Another reason was that my wife wouldn't ride in the car any more because she thought it was too loud. It was cheaper for me to get a new exhaust. ![GTFO](https://ls1tech.com/forums/images/smilies/gtfoslap.gif)
To all those out there with GMMG - I'm not bashing! It's a bad *** sounding system that flows really well. The Mufflex sounds pretty good too with plenty of volume, but is not as aggressive as the GMMG. Another bonus, is now I can actually hear my supercharger!
More opinions welcome!
![GTFO](https://ls1tech.com/forums/images/smilies/gtfoslap.gif)
To all those out there with GMMG - I'm not bashing! It's a bad *** sounding system that flows really well. The Mufflex sounds pretty good too with plenty of volume, but is not as aggressive as the GMMG. Another bonus, is now I can actually hear my supercharger!
More opinions welcome!
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#17
TECH Senior Member
iTrader: (39)
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http://www.thirdgen.org/techboard/ex...ml#post3712408
I just had a 4inch mufflex installed on my 3rd gen. Whats the part number for the magnaflow muff? Thanks.
I just had a 4inch mufflex installed on my 3rd gen. Whats the part number for the magnaflow muff? Thanks.
#18
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http://www.thirdgen.org/techboard/ex...ml#post3712408
I just had a 4inch mufflex installed on my 3rd gen. Whats the part number for the magnaflow muff? Thanks.
I just had a 4inch mufflex installed on my 3rd gen. Whats the part number for the magnaflow muff? Thanks.