GMMG RWHP gain??
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Teching In
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GMMG RWHP gain?? (Sorry if this had been asked)
Hey you GMMG guys...i'm saving up to get one of 'em...but nevermind that i was wondering what is the avg. of RWHP the GMMG owners got?
Any numbers would help a lot and i would be greatly appreciated!
Thank You
Hey you GMMG guys...i'm saving up to get one of 'em...but nevermind that i was wondering what is the avg. of RWHP the GMMG owners got?
Any numbers would help a lot and i would be greatly appreciated!
Thank You
gain from catback if you're talking gain from just a catback, I think those numbers are way high. most you can expect, to the best of my knowledge is maybe 10 RWHP. More likely a lot closer to 5 RWHP. Despite what a lot of beginners think (myself included at one point) a catback is more about sound than speed. 
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From: Fairbanks, AK
Originally Posted by FenixSS
I haven't dynoed yet, but the installation sheet says "depending on the set up, anywhere from at least 20HP to as much as 50HP."
Jeez, that's worse than SLP's claims. 
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Joined: Oct 2002
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From: Long Island, NY
Originally Posted by mako22
if you're talking gain from just a catback, I think those numbers are way high. most you can expect, to the best of my knowledge is maybe 10 RWHP. More likely a lot closer to 5 RWHP. Despite what a lot of beginners think (myself included at one point) a catback is more about sound than speed.
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Guys, the last batch of intructions printed had a typo. It reads gain 50 to 20 horsepower. It should read 5 to 20 horsepower. As said above, catbacks are more for sound, than performance. The GMMG will definately give you a noticable SOTP gain, just not 50rwhp 
Hope this helps a lil
Hope this helps a lil
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Teching In
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Yes, all of the post helped me out a lot...although 50 hp?! WHOA...that is way more than what SLP says...25hp..although i dont believe any of it..i know its within the 5-20 RWHP (depending on application). But i was just wondering what you guys got with just a GMMG...just out of curiosity...
Thank all of you LS1tech ers
Thank all of you LS1tech ers
Well i had the SLP dual/dual so it flowed good already.. but i picked up 6 rwhp over that.. also keep in mind that I only picked up 3-4 rwhp with my cutout open so the GMMG must be a pretty free-flowing exhaust.
Oh and it sounded so good people would follow me home
Im working on a version for my 69..
Oh and it sounded so good people would follow me home
Im working on a version for my 69..
DOH, I thought it was just backwards Oh well, gain is gain, and you just can't beat the sound
Oh well, gain is gain, and you just can't beat the sound
Originally Posted by Cammin BeaSSt
Guys, the last batch of intructions printed had a typo. It reads gain 50 to 20 horsepower. It should read 5 to 20 horsepower. As said above, catbacks are more for sound, than performance. The GMMG will definately give you a noticable SOTP gain, just not 50rwhp
Hope this helps a lil
Hope this helps a lil
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Joined: Nov 2002
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From: Lincolnton, NC
You will not see any SOTP gain. The WS6 and SS exhaust is quiet good out of the box. I would believe Z28's and TA's would be closer to that 10-12rwhp gain. As for a horsepower gain advertised I have never seen ONE claim by GMMG much less one for 20-50rwhp for a catback.
Originally Posted by 4mula
youre one of the very lucky and few to see those kinda numbers on a stock car.
5 to 20 is extremely typical depending on the setup.
) Overall I couldn't really feel much of a difference BUT the SOUND OMG 
