Gut Cats and Stock Manifolds
Gut Cats and Stock Manifolds 
02-02-2004, 11:52 AM
#2
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I was thinking the samething. I reserched it on this board. They said that there would be alot of rasp (interior and exterior noise) because of the cats being hollow. Meaning that the exhaust gas will expand in the casing empty cats this will cause turbulance and it will circulate and disrupt flow abit but not too badly.
They said to expect at the least about a 5 hp increase. With a tenth improvement.
Hope this helps,
Adam
2002 T/A Firehawk #536 M6
They said to expect at the least about a 5 hp increase. With a tenth improvement.
Hope this helps,
Adam
2002 T/A Firehawk #536 M6
02-02-2004, 01:11 PM
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Another option is offroad tubes that replace the cats
(Mufflex; others?). This is an 8-bolt swap if you have
some concern with emissions testing, easy to do once
a year.
Gains are to be had from port-matching the exhaust
manifolds; as-cast they intrude into the port quite a
bit. Now you're getting close to the effort of header
install (but closing the gap between stock logs and
shorties as well).
(Mufflex; others?). This is an 8-bolt swap if you have
some concern with emissions testing, easy to do once
a year.
Gains are to be had from port-matching the exhaust
manifolds; as-cast they intrude into the port quite a
bit. Now you're getting close to the effort of header
install (but closing the gap between stock logs and
shorties as well).
02-02-2004, 02:27 PM
#6
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with my shock cats on i went to 13.52 @ 105 with the gutted cat i went 12.89@108 et slick with LM replace with dynomax so it 's up to you ...there' rasp noise by way stock ls1 can go high 12 ez to twista 
to you
to you Last edited by 2KSSLS1; 02-03-2004 at 04:17 PM.
02-02-2004, 03:40 PM
#7
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I already have the Sims and my buddy's shop is charging me 50 bucks to gut the cats but If its going to sound nasty then I might think of other alternatives. I wanted those new cheap headers but some advise me to swap my clutch first then the headers because they will be in the way.
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02-02-2004, 03:48 PM
#8
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Originally Posted by 2KSSLS1
with my shock cats on i went to 13.52 @ 105 with the gutted cat i went 12.89@108 with LM replace with dynomax so it 's up to you ...there' rasp noise
There is no way you gained 6 tenths by just gutting the cats
!!
02-02-2004, 03:57 PM
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Originally Posted by TWISTA TA
There is no way you gained 6 tenths by just gutting the cats !!
!!
02-03-2004, 12:35 AM
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Originally Posted by jimmyblue
Another option is offroad tubes that replace the cats
(Mufflex; others?). This is an 8-bolt swap if you have
some concern with emissions testing, easy to do once
a year.
Gains are to be had from port-matching the exhaust
manifolds; as-cast they intrude into the port quite a
bit. Now you're getting close to the effort of header
install (but closing the gap between stock logs and
shorties as well).
(Mufflex; others?). This is an 8-bolt swap if you have
some concern with emissions testing, easy to do once
a year.
Gains are to be had from port-matching the exhaust
manifolds; as-cast they intrude into the port quite a
bit. Now you're getting close to the effort of header
install (but closing the gap between stock logs and
shorties as well).
02-04-2004, 11:35 AM
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Originally Posted by greekss
where do i get these replacement cat tubes ???
https://ls1tech.com/forums/generation-iii-external-engine/135136-best-affordable-y-pipe.html
02-04-2004, 04:33 PM
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Originally Posted by Chris ARE 360
I would just buy a MAC ORY for the stock manifolds. Stock Ypipe with cats is worth a bit of money if you want to sell it 
02-04-2004, 06:13 PM
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Originally Posted by 98SS Blackattack
