2012 GS Exhaust Question
Thread Starter
Pro
Joined: Aug 2007
Posts: 562
Likes: 2
From: Jacksonville FL
2012 GS Exhaust Question
On the Grand Sport, there are the two factory cats connected to the exhaust manifolds. But on the X Pipe at the front it looks like there are two additional cats as part of the X pipe but just forward of the X part. What are these exactly and what are they used for?
Thanks.
Thanks.
Team Owner
Joined: Sep 2005
Posts: 20,352
Likes: 568
From: Ventura County, Calif
Melting Slicks
Joined: Dec 2006
Posts: 2,694
Likes: 106
Those extra cats shouldn't affect any aftermarket exhaust fitment, since both X-pipes have identical dimensions. Since I don't live in CA, I converted my 2012 into a 2011 
. They look 100% OEM because they are 
. The heat in the center console is still there but tolerable now, and NPP open sounds louder 
. I bought new gaskets ($$), but don't think they were necessary. By the way, bought them from forum member (and vendor) JJFormato. As far as weight savings, don't remember exactly (search under my name, since I posted that a few months ago), but I want to think 18 lbs. Not that much, but a nice savings. Here they are side by side:
. They look 100% OEM because they are . The heat in the center console is still there but tolerable now, and NPP open sounds louder . I bought new gaskets ($$), but don't think they were necessary. By the way, bought them from forum member (and vendor) JJFormato. As far as weight savings, don't remember exactly (search under my name, since I posted that a few months ago), but I want to think 18 lbs. Not that much, but a nice savings. Here they are side by side:
Last edited by JCtx; Sep 24, 2012 at 10:43 PM.
Intermediate
Joined: Dec 2013
Posts: 49
Likes: 3
From: Kansas City MO
Those extra cats shouldn't affect any aftermarket exhaust fitment, since both X-pipes have identical dimensions. Since I don't live in CA, I converted my 2012 into a 2011 . They look 100% OEM because they are . The heat in the center console is still there but tolerable now, and NPP open sounds louder . I bought new gaskets ($$), but don't think they were necessary. By the way, bought them from forum member (and vendor) JJFormato. As far as weight savings, don't remember exactly (search under my name, since I posted that a few months ago), but I want to think 18 lbs. Not that much, but a nice savings. Here they are side by side:
. They look 100% OEM because they are . The heat in the center console is still there but tolerable now, and NPP open sounds louder . I bought new gaskets ($$), but don't think they were necessary. By the way, bought them from forum member (and vendor) JJFormato. As far as weight savings, don't remember exactly (search under my name, since I posted that a few months ago), but I want to think 18 lbs. Not that much, but a nice savings. Here they are side by side:Just saw this old thread but looks like something I would like to do to my 13 GS. Do you have the part number for the x-pipe without the cats? thanks - KC Slider
Racer
Joined: Dec 2001
Posts: 388
Likes: 1
From: Shakedown Street,Buffalo N.Y.
How many cel are the primary cats and secondary cats. The primary are probably higher count, there for higher restriction. Add that to being closer to the motor, more gains may be had by getting rid of the primary cats and retaining the secondary set to keep the stink out. You would just have to have the car tuned to not monitor the primary cats anymore.
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Instructor
Joined: Aug 2013
Posts: 145
Likes: 5
From: Raleigh, NC
Don't know the ratings; however, yes, the only ones that will trigger a light is the front set. The rears are smaller and can be removed with no problem. The issue is that on the 2012 GS, not sure what other years, the primary cats are built into the manifold. Only option to get rid of them is to do a swap to headers.