A More Quiet GMMG
Put a Moroso Spiral flow in the I-pipe. I have had both a moroso and a dynomax bullet. The sprial flow gets rid of the rasp and drone. Voted best sounding car by the SCCA officals at the track I was road racing at. The dyno max gets rid of the drone but sounds like **** between 2000 and 3000 and is much louder. John
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From: Citrus Heights, CA
Originally Posted by Ojustracing
Put a Moroso Spiral flow in the I-pipe. I have had both a moroso and a dynomax bullet. The sprial flow gets rid of the rasp and drone. Voted best sounding car by the SCCA officals at the track I was road racing at. The dyno max gets rid of the drone but sounds like **** between 2000 and 3000 and is much louder. John
I have the Dyno max on the car right now and cant make it to the dyno before I go back to the track. Lime Rock has a 95 DB limit and I dont think this muffler is going to meet that at WOT!!!!!!!!!!
John
John
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From: Citrus Heights, CA
Originally Posted by Ojustracing
I have the Dyno max on the car right now and cant make it to the dyno before I go back to the track. Lime Rock has a 95 DB limit and I dont think this muffler is going to meet that at WOT!!!!!!!!!!
John
John
Red let me put it this way to you. I had the exhaust with no cats, Moroso Sprial flow, and the dynomax in that order. The no cats the car was stupid loud, lots of rasp and drone was horrible. The Moroso took care of 98% of the drone, no rasp. Sounds like a v-8 should through the whole rpm range. Now I have the dyno-max. Lots of rasp, drone is back but on the line of being unbearable and its loud again too much for me, exhaust starting to sound like **** again.
JFYI I race the car in the Cannonball One Lap Of America, we covered 7500+ miles in 9 days. I know what I can get away with during the wk for exhaust noise and the dyno max isnt going to cut it.
John
JFYI I race the car in the Cannonball One Lap Of America, we covered 7500+ miles in 9 days. I know what I can get away with during the wk for exhaust noise and the dyno max isnt going to cut it.
John
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From: Citrus Heights, CA
Originally Posted by Ojustracing
Red let me put it this way to you. I had the exhaust with no cats, Moroso Sprial flow, and the dynomax in that order. The no cats the car was stupid loud, lots of rasp and drone was horrible. The Moroso took care of 98% of the drone, no rasp. Sounds like a v-8 should through the whole rpm range. Now I have the dyno-max. Lots of rasp, drone is back but on the line of being unbearable and its loud again too much for me, exhaust starting to sound like **** again.
JFYI I race the car in the Cannonball One Lap Of America, we covered 7500+ miles in 9 days. I know what I can get away with during the wk for exhaust noise and the dyno max isnt going to cut it.
John
JFYI I race the car in the Cannonball One Lap Of America, we covered 7500+ miles in 9 days. I know what I can get away with during the wk for exhaust noise and the dyno max isnt going to cut it.
John
Thanks man! No dynomax for me! Guess I'll try the magnaflow..........
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From: Citrus Heights, CA
Originally Posted by black01_WS6
so have you decided what route you are going to take?
I think I'll give the magnaflow a shot, and if that doesn't work I'll consider swapping to another catback.
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Originally Posted by Redneck Z
I think I'll give the magnaflow a shot, and if that doesn't work I'll consider swapping to another catback.
They are only like 50-70 bucks too. A true 3" inner diameter flow path(no sacrificing flow) and it will help tremendously! Get a 20" muffler and have it welded into the i-pipe. That would tone down the loudness but you'll retain that badass sound.
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From: Citrus Heights, CA
Originally Posted by black01_WS6
the cat back or muffler? and if you were to get rid of the gmmg how much would you want for it?
Just a 3" I/O round muffler in the I. I'll have to give the $$ some thought.
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From: Citrus Heights, CA
Originally Posted by lilbuddy1587
Like I said, if you want to keep that sweet chambered sound but more tame and not as loud: http://www.classicchambered.com/classic/products.html
They are only like 50-70 bucks too. A true 3" inner diameter flow path(no sacrificing flow) and it will help tremendously! Get a 20" muffler and have it welded into the i-pipe. That would tone down the loudness but you'll retain that badass sound.
They are only like 50-70 bucks too. A true 3" inner diameter flow path(no sacrificing flow) and it will help tremendously! Get a 20" muffler and have it welded into the i-pipe. That would tone down the loudness but you'll retain that badass sound.
I've gone back and forth between the powerstick and magnaflow. I figured the magnaflow would have more sound reduction with it's stainless steel packing. I could almost go either way. Too bad no one else has done this to their GMMG!
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From: Citrus Heights, CA
Originally Posted by userws6
Have you smogged your car yet with the LT's, if so how much trouble was it? I would also be intrested in the gmmg if you do decide to get rid of it, and would come pick it up, maby tonite?
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I spent a great deal of time quieting my GMMG after LTs, catted y and cam:
- Dyno max doesn't quiet it much
- Borla 5" round just fits and quiets it quite a bit but changes the sound
- Stainless works will make you a chambered section for the I pipe that runs from Y to the bend that goes up over the axle for about the same price as the Borla (I think it's about 24" long). Quiets it down, and keeps the chambered sound.
- GMMG will sell you a replacement I pipe for $100 if you're worried about restoring it to original.
- Dyno max doesn't quiet it much
- Borla 5" round just fits and quiets it quite a bit but changes the sound
- Stainless works will make you a chambered section for the I pipe that runs from Y to the bend that goes up over the axle for about the same price as the Borla (I think it's about 24" long). Quiets it down, and keeps the chambered sound.
- GMMG will sell you a replacement I pipe for $100 if you're worried about restoring it to original.
Originally Posted by DaddySS
I spent a great deal of time quieting my GMMG after LTs, catted y and cam:
- Dyno max doesn't quiet it much
- Borla 5" round just fits and quiets it quite a bit but changes the sound
- Stainless works will make you a chambered section for the I pipe that runs from Y to the bend that goes up over the axle for about the same price as the Borla (I think it's about 24" long). Quiets it down, and keeps the chambered sound. - GMMG will sell you a replacement I pipe for $100 if you're worried about restoring it to original.
- Dyno max doesn't quiet it much
- Borla 5" round just fits and quiets it quite a bit but changes the sound
- Stainless works will make you a chambered section for the I pipe that runs from Y to the bend that goes up over the axle for about the same price as the Borla (I think it's about 24" long). Quiets it down, and keeps the chambered sound. - GMMG will sell you a replacement I pipe for $100 if you're worried about restoring it to original.
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From: Citrus Heights, CA
Originally Posted by userws6
You say the longtubes, head/cam go on friday. if you are replacing it with origional parts that should quiet it up from what i've heard.
Come again? Original parts? I'm doing a different heads cam setup than I already have, and longtubes with my GMMG. I don't have any "quiet parts" lol.
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From: Citrus Heights, CA
Originally Posted by DaddySS
I spent a great deal of time quieting my GMMG after LTs, catted y and cam:
- Dyno max doesn't quiet it much
- Borla 5" round just fits and quiets it quite a bit but changes the sound
- Stainless works will make you a chambered section for the I pipe that runs from Y to the bend that goes up over the axle for about the same price as the Borla (I think it's about 24" long). Quiets it down, and keeps the chambered sound.
- GMMG will sell you a replacement I pipe for $100 if you're worried about restoring it to original.
- Dyno max doesn't quiet it much
- Borla 5" round just fits and quiets it quite a bit but changes the sound
- Stainless works will make you a chambered section for the I pipe that runs from Y to the bend that goes up over the axle for about the same price as the Borla (I think it's about 24" long). Quiets it down, and keeps the chambered sound.
- GMMG will sell you a replacement I pipe for $100 if you're worried about restoring it to original.
Yeah, I didn't want the Borla because I'd lose too much clearance with it being 5". I've thought about a stainless works or power stick, but didn't think it'd quiet it down enough. That's basically what the SW chambered catback is right? They are similar to the GMMG only with a chambered muffler in the I pipe I believe, and are pretty loud?? Do you have a SW's in your I pipe right now? If so, how much did it quiet it? Does it still sound the same, only more quiet?
Well, I have a Powerstick in my I-pipe with a cutout after the axle and it didn't really quiet my car down much at all. It may be slightly quieter, but the real change was in sound quality. If you're looking for sound reduction, I'm not sure a Powerstick will help much.