I'm making a totally custom catback for the Z this weekend, based off GMMG
#1
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Im new, but some of you may be interested. I fabricate custom exhausts for my own personal vehicles, and I fell in love with the GMMG exhaust note on F-bodies. At my work, we make very similar mufflers to use on the new GTOs. So im piecing together a custom, made from scratch overaxle back, using the magnaflow 3" pipe from the Y pipe to the overaxle together with my custom straight through chambered mufflers and misc. mandrel SS bends, i'm gonna replicate the GMMG from the overaxle back, re-using the magnaflow polished SS tips. The car has edelbrock headers, magnaflow system, and i believe the stock Y with stock cats (soon to be changed).
I'll put pics/sounds up this weekend after i get it all done.
UPDATE:
Now i know its not perfect (like the tips but you can't tell unless you really look at it), but it functions great. Retightened the clamps today and added braces. All ready for E-check and summer now![Tongue](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_tongue.gif)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0157666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0158666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0159666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0160666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0161666.jpg)
I'll put pics/sounds up this weekend after i get it all done.
UPDATE:
Now i know its not perfect (like the tips but you can't tell unless you really look at it), but it functions great. Retightened the clamps today and added braces. All ready for E-check and summer now
![Tongue](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_tongue.gif)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0157666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0158666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0159666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0160666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0161666.jpg)
![](http://i36.photobucket.com/albums/e6/ExpodingGopher/100_0162666.jpg)
Last edited by ExplodingGopher; 01-28-2007 at 12:29 PM.
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I always wanted to take an old Loudmouth put a sweet thinder chambered muffler in place of the resonator, then one right after the axle where it crosses over to the driver side and then one between the axle and the bumper cover on the ps.
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I make custom systems for a living at Stainless Works. So this is a walk in the park for me ![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
I hope i will get a significant increase in loudness over the magnaflow system, even with the stock cats still on. Its just waaaaay too quiet for me.
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I hope i will get a significant increase in loudness over the magnaflow system, even with the stock cats still on. Its just waaaaay too quiet for me.
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Originally Posted by ExplodingGopher
I make custom systems for a living at Stainless Works. So this is a walk in the park for me ![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
I hope i will get a significant increase in loudness over the magnaflow system, even with the stock cats still on. Its just waaaaay too quiet for me.
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
I hope i will get a significant increase in loudness over the magnaflow system, even with the stock cats still on. Its just waaaaay too quiet for me.
http://www.stainlessworks.net/cart/p...roducts_id=819
I also have a GMMG exhaust if you want a clip let me know. It does not have stock cats and manifolds and such however.
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Now this is just my .02...... I've seen it installed on an F-body, our chambered system is very different, it consists of 3 mufflers actually, IMHO, i don't like the way it looks on the back end, you can see the mufflers as they are directly in front of the tips. It does, however, seem to be more free-flowing than my custom system. Either way, im still making mine from scratch based off GMMG. I like a good challenge
. I'll probably just see how it sounds through the edelbrock shorties, new cats and stock Y pipe for now.
Im thinking i'm gonna install the high flow cats that i bought from my friend where the stockers are located too this weekend.
I'll post pics tomarrow if the weather permits the install.
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
Im thinking i'm gonna install the high flow cats that i bought from my friend where the stockers are located too this weekend.
I'll post pics tomarrow if the weather permits the install.
Last edited by ExplodingGopher; 01-26-2007 at 08:34 PM.
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sounds neat, i agree the sound of a gmmg is
i have clips but none are on my computer yet. People complain about the price but I have yet to hear a better sounding catback. Which magnaflow tips are you using, the catback ones or the kind you can buy separate, maybe i misread something.
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#14
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Well, it was a complete success, looks pretty much just like the GMMG system, a few changes here and there, has a very very deep rumble at idle, really lets loose behind the car when revved.....just with edelbrock shorties and stock cats/Y pipe. Its nice and quiet in the car when driving, loud/deep outside.
PICS GOING UP TOMARROW SINCE ITS DARK OUT AND IM PRETTY TIRED
PICS GOING UP TOMARROW SINCE ITS DARK OUT AND IM PRETTY TIRED
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Last edited by ExplodingGopher; 01-27-2007 at 06:55 PM.
#16
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PICS ADDED AT THE TOP POST.......... Im not going to say exactly how much i spent on it, but with my friend selling me the clamps and some bends, and with SW mufflers.... it was less than $100....plus about 5 hours of fabricating/welding
I'll post sound clips when it gets warmer out...
I'll post sound clips when it gets warmer out...
#17
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nobody likes it? I know the tips aren't perfect, but hey it cost waaaaaay less than a GMMG lol. PLus i'll end up fixing the tips when its warmer out anyways because it bothers me.
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I think as long as you are happy with it then that's all that matters. Personally I think it looks good, but not great. That's just because I'm **** about stuff. I would have taken it all off the car and grinded down the welds and polished it or painted it, but that's just me. I can't wait to hear the sound clip. With it being cold it will actually sound great when you first start it up.
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i also fabed up a custom cat-back... i have a formula tho, and can't stand how formulas look with dual exhaust, so i wanted a SLP 2otl but couldn't justify the $500 price tag. so i made my own 2otl with two 18'' sweet thunders it ended up costing $150 for everything, down the road, still sounded like a LT-1 with a cat-back ( a ****** pickup truck ) so now i have LT's and a Flowmaster 1otl... PICS OF THE CUSTOM SET UP:
![](http://memimage.cardomain.net/member_images/1/web/2161000-2161999/2161580_51_full.jpg)
![](http://memimage.cardomain.net/member_images/1/web/2161000-2161999/2161580_51_full.jpg)
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