Need Advise on Cats - ZR-1 Net Registry Forums

Jagdpanzer · 02-06-2008

Like a few of you guys I'm about ready to install a set of headers and performance exhaust system on my Z. However, in my case I'm still looking for the right cats to go with. On this forum I read where a lot of you have gone with Random Tech bullet cats. Here are a few questions I hope those of you with more experience can help me with:
What advantages do the RT bullet cats have over the others available?
Which particular RT model and size is best to use?
Which core type is better, ceramic or metal matrix?
Should some sort of flange connection be installed between header discharge and the cats or should everything be welded solid like Nick did? http://www.pnwzr1.net/Nick/Headers/Headers%20049.JPG
Is heat insulation or shielding of the cat necessary?
Where is a good place to buy RT bullet cats?
Are there any other cat manufactures out there I should be also taking a look at?
Pics would be most appreciated
Thanks

02-06-2008

DO NOT WELD THEM IN!!! It makes for a huge headache when you need to remove the exhaust later on. Find a competent exhaust shop that can give you some flanges.

Take a look at the magnaflow cats. Cheaper than the RT cats, and they are the same thing. You can hold each in your hand and you can not tell the difference other than the name stamping.

GrayZ · 02-06-2008

I have RT'S but if i would have seen these below first, well...i dunno
meow

kenthompson · 02-07-2008

Quote:

Originally Posted by ITLGO2

I have RT'S but if i would have seen these below first, well...i dunno
meow

I can see where heat is going to be an issue. I hope the inlet/outlet size is appropriate. Do you think the noise issue will go away?

tccrab · 02-07-2008

Quote:

Originally Posted by kenthompson

I can see where heat is going to be an issue. I hope the inlet/outlet size is appropriate. Do you think the noise issue will go away?

Sorry, those Cats will cause you nothing but trouble. If they ever need replacing it will cost you a fortune!

DMark · 02-07-2008

Quote:

Originally Posted by Jeffvette

..... Take a look at the magnaflow cats. Cheaper than the RT cats, and they are the same thing.....

Hey Jeff,

Would you happen to know the Magnaflow part # that would work with SW headers?

Thanks,

tf95ZR1 · 02-07-2008

You can get them from a place like Summitt or Jegs.
Just name your diameter in and diameter out.
ie 3 in / 3 in

Nick · 02-07-2008

I don't mind the CATs being welded in. IF I ever need to drop the trans, I'll deal with the issue at that time (probably by removing the headers, which ain't all that bad a job; certainly no where near the hassle of removing the stock manifolds!). Having the CATS welded in beats having to replace leaky and noisy exhaust header collector gaskets every oil change, like I used to do on my '55 Bel Air when it had headers.

tf95ZR1 · 02-07-2008

Hey Nick
Flanges probably would be the neatest, but are they necessary?
My cats are slip fitted and clamped. They haven't loosened but
the day ain't over yet.......

If there was a problem with loosening I'd just tack weld them in a
few spots. Easy to grind down for removal.
Ted

Nick · 02-09-2008

Ted, I think the slip fit with clamps is fine. A few small tack welds would be awesome, and certainly not permanent like mine.

02-06-2008	#1
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,661	Need Advise on Cats Like a few of you guys I'm about ready to install a set of headers and performance exhaust system on my Z. However, in my case I'm still looking for the right cats to go with. On this forum I read where a lot of you have gone with Random Tech bullet cats. Here are a few questions I hope those of you with more experience can help me with: What advantages do the RT bullet cats have over the others available? Which particular RT model and size is best to use? Which core type is better, ceramic or metal matrix? Should some sort of flange connection be installed between header discharge and the cats or should everything be welded solid like Nick did? http://www.pnwzr1.net/Nick/Headers/Headers%20049.JPG Is heat insulation or shielding of the cat necessary? Where is a good place to buy RT bullet cats? Are there any other cat manufactures out there I should be also taking a look at? Pics would be most appreciated Thanks Last edited by Jagdpanzer; 02-06-2008 at 11:06 PM.

02-06-2008	#2
Jeffvette Guest Posts: n/a	Re: Need Advise on Cats DO NOT WELD THEM IN!!! It makes for a huge headache when you need to remove the exhaust later on. Find a competent exhaust shop that can give you some flanges. Take a look at the magnaflow cats. Cheaper than the RT cats, and they are the same thing. You can hold each in your hand and you can not tell the difference other than the name stamping.

02-06-2008	#3
GrayZ Join Date: Mar 2006 Location: Innsbrook, Missouri Posts: 1,727	Re: Need Advise on Cats I have RT'S but if i would have seen these below first, well...i dunno meow

02-07-2008	#7
tf95ZR1 Join Date: Aug 2005 Location: Northridge, CA Posts: 1,461	Re: Need Advise on Cats You can get them from a place like Summitt or Jegs. Just name your diameter in and diameter out. ie 3 in / 3 in

02-07-2008	#8
Nick Join Date: Jul 2005 Location: Auburn, Washington Posts: 586	Re: Need Advise on Cats I don't mind the CATs being welded in. IF I ever need to drop the trans, I'll deal with the issue at that time (probably by removing the headers, which ain't all that bad a job; certainly no where near the hassle of removing the stock manifolds!). Having the CATS welded in beats having to replace leaky and noisy exhaust header collector gaskets every oil change, like I used to do on my '55 Bel Air when it had headers. __________________ Nick ZR-1 Net Registry Founding Member #32 - lapsed...

02-07-2008	#9
tf95ZR1 Join Date: Aug 2005 Location: Northridge, CA Posts: 1,461	Re: Need Advise on Cats Hey Nick Flanges probably would be the neatest, but are they necessary? My cats are slip fitted and clamped. They haven't loosened but the day ain't over yet....... If there was a problem with loosening I'd just tack weld them in a few spots. Easy to grind down for removal. Ted

02-09-2008	#10
Nick Join Date: Jul 2005 Location: Auburn, Washington Posts: 586	Re: Need Advise on Cats Ted, I think the slip fit with clamps is fine. A few small tack welds would be awesome, and certainly not permanent like mine. __________________ Nick ZR-1 Net Registry Founding Member #32 - lapsed...