View Full Version : Stock Cats with aftermarket exhaust

05-03-05, 11:18 PM
Anyone consider ditching the cats or hollowing them out? Not sure if the loss in back pressure would be a good thing or not. I imagine that it would sound a lot nicer. I did some searching around and it seems that a lot of Z06 guys are running without cats. Thoughts?

I know, just give in and buy the B&B Headers... But in the mean time, do you think this would be a good idea?

05-03-05, 11:22 PM
Random Tech cats....very nice...easy install...200 cells/in vs. stock @ 500 cells/in = more flow.


05-03-05, 11:24 PM
Personally, I like to breathe good air. :)

05-03-05, 11:31 PM
According to Random Tech web site:

"Under Federal EPA regulation, replacement of original catalytic converters is allowed only if the original converter(s) is missing, or the vehicle has more than 50,000 miles or is at least five years old and the need for a replacement has been established and documented, or a local inspection program has determined the existing converter is in need of replacement. Please note that no aftermarket catalytic converters are legal for installation in California on OBD II vehicles (some 1994 & 1995, and all 1996 and later vehicles)."

So if it's already illegal to replace them on a new car then why not just remove them all togather? :devil:

Also 0 cells/in vs. stock @ 500 cells/in = EVEN more flow :D

Just not sure if hollowing out the cats is the right way to go.

05-03-05, 11:52 PM
Hey Dans, I've been hoping to meet up with another V owner with a Corsa, or even more so, a B&B catback. I'm assuming your close since I saw you in Tewksbury the other week. Not a big deal if I creep you out, but if you'd be up to meet, I'd love to hear it.

I've debated between the 2 but I must admit, am decidedly more drawn to the B&B. Plus the headers look great. Maybe Billy can get me a discount for buying both together.

05-04-05, 12:02 AM
R U guys subject to visual inpections where you are, I see this as a major consideration.

05-04-05, 12:17 AM
R U guys subject to visual inpections where you are, I see this as a major consideration.

Money talks. :sneaky:

05-04-05, 08:16 AM
I have never had an inspection tech look under any of my vehicles here in Mass in the last 7 or 8 years.. I think it depends on what you look like and what you drive sometimes...

05-04-05, 08:29 AM
A few other considerations: Altering the cats in any way likely will result in triggering the idiot light due to oxygen sensors . . . also be carefull if you are going to attempt to clean the cats out as there are a number of metalic substances (some of which are preciuous metals like platinum) in there and any dust created is probably not good to take in.

05-04-05, 11:38 AM
My thought was to clean them out so by a visual inspection, they would still be there. Just wondering if there would be any benefit to it. I am sure it would sound better. Those cats are restrictive. I would be concerned if it would cause the idiot light to come on.

Jim - I wouldn't mind meeting up some time. Right now I have the B&B Exhaust with the resonator on. B&B shipped that to me by mistake as I ordered the XPIPE. They are shipping out the XPIPE today. I probably won't get it until mid next week though. So if you want to hear the resonator we should meet up this week. If you want to hear the XPIPE then we can wait.

05-04-05, 07:16 PM
I have been thinking of running without my cats (live in SC...no inspection of any kind) only issue might be dealer visits. Removal would be combined with PCM tune. Any performance to be gained?

05-04-05, 10:20 PM
VinCLT...where do you live in SC? e-mail me at jmed99@hotmail.com. Your PMs are off.

Sorry...not trying to highjack!