STS and Cats
Thread Starter
On The Tree
Joined: Apr 2007
Posts: 182
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STS and Cats Ok, I have heard numerous people talk about it being bad to keep your cats with the STS turbo kit, but you have to have cats in my state(at least I think you do), and thought I've heard people say that they have heard of the cats melting and ******* up the turbo, I have never seen a thread on it or heard of it in any way first hand.
My question is, is having the cats on a really big deal, or is it just something that happenned once and now gets over exaggerated?
If anyone has any suggestions to where I can lose the cats and pass inspection, let me know.
My question is, is having the cats on a really big deal, or is it just something that happenned once and now gets over exaggerated?
If anyone has any suggestions to where I can lose the cats and pass inspection, let me know.
Now as far as emissions test... Most people pass with out cats with this system.. It DOES NOT have a Carb Number..
Just have it running really lean (and I mean ONLY WHEN YOUR GETTING SNIFFED), when you get sniffed, and then MAKE SURE TO TUNE IT BACK REGULARLY before driving it agian....
Just have it running really lean (and I mean ONLY WHEN YOUR GETTING SNIFFED), when you get sniffed, and then MAKE SURE TO TUNE IT BACK REGULARLY before driving it agian....
I've never heard of a stock cat chunking out the exhaust, however it's happened to me with aftermarket cats only making 350rwhp. The worst I've heard of happening to stock cats is them melting, but that won't mess up the turbo.
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If you have to have cats to pass smog I don't see why you're even asking... You will have to keep them on obviously. Unless you buy a off road y-pipe and swap the stock back on for smog. That always works. I know lots of guys that run cats with the STS turbo. It's a little risky yes, if that cat breaks apart, good bye turbo. But how often do you hear of cats breaking on their own(without an impact)? I'd suggest putting a screen in pre-turbo, but that might create some restriction and probably wouldnt stop the small pieces of cat that come through.
Launching!
Joined: Feb 2007
Posts: 297
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From: Tucson
I just welded a pair of flowmasters on my buddies car.
He bought them used for a good deal.........well there was a lot of carbon buildup so I took a dead blow hammer and tapppd them a little. Dude chunks of cat started falling out, the size of golf ***** to really small chunks. Cat do fail and that could be you 6 or 7 hundered dollar turbo. not worth keeping them.
He bought them used for a good deal.........well there was a lot of carbon buildup so I took a dead blow hammer and tapppd them a little. Dude chunks of cat started falling out, the size of golf ***** to really small chunks. Cat do fail and that could be you 6 or 7 hundered dollar turbo. not worth keeping them.
Staging Lane
Joined: Jan 2006
Posts: 88
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I don't know about your area, but in NJ and Pa they only do a scan of the car (obd2), no running test. If the check engine light is not on and there are no more than 2 readiness tests incomplete the car will pass. They still do a visual, but a lot of people don't pay very close attention or you can have a gutted shell there so it looks like it has cats
Originally Posted by jeremy02
Anyone know any mechanics in NC that will pass me catless?
As far as keeping the cats on IMO that is out of the question. I worked in the exhaust business for many years and most of the cats that I have seen fail have sent chunks down the system. Cats are "lifetime" parts which means that they "should" last at least 10years/100Kmiles 
. They may not fail on you soon, but they will eventually, and then you're buying a new turbo. If I were you I'd get real friendly with a local inspector. 
. They may not fail on you soon, but they will eventually, and then you're buying a new turbo. If I were you I'd get real friendly with a local inspector. 
TECH Addict
Joined: Aug 2004
Posts: 2,866
Likes: 4
Originally Posted by T A WS6 M6
As far as keeping the cats on IMO that is out of the question. I worked in the exhaust business for many years and most of the cats that I have seen fail have sent chunks down the system. Cats are "lifetime" parts which means that they "should" last at least 10years/100Kmiles . They may not fail on you soon, but they will eventually, and then you're buying a new turbo. If I were you I'd get real friendly with a local inspector.
. They may not fail on you soon, but they will eventually, and then you're buying a new turbo. If I were you I'd get real friendly with a local inspector. thanks Chris.
Thread Starter
On The Tree
Joined: Apr 2007
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Originally Posted by Travis99LS1
Hey man..In NC there is a visual check for cats...Now whether or not they do it thats a different story. NC is an OBD inspection..there gonna hook up to the OBD port and if there's any codes it will fail. If you get rid of your cats, get O2 simulators, this way the PCM wont throw a code for the cats..and you'll be able to pass. If you gut them, then even if they look under the car they will think you have cats. There isnt any type of exhaust sniffer for emissions anymore in carolina, so your good there. NC is actually kind of strict about there inspections...Either way, you cant have your check engine light on and get passed. What we used to do to get cars passed that had check engine lights, we would scan the barcode on your registration..than you VIN # would come into the computer..than we would just take another car that would pass, and hook the OBD connector to it. It would run the inspection, and pass the car..But when it got sent to the state, it would come up as whatever car you scanned the registration on. They caught onto this, and now when you hook up to the car..it reads the VIN# from the car..and if it doesent match the registration the inspector can get a pretty big fine, and the car doesent pass...I dont know where you are in NC..but let me know if you cant find anyone to pass you..I might be able to help you out.
I live about 45 minutes from Charlotte. I might be hittin you up.
Originally Posted by chuntington101
what are your impressions on the matalic cats that you can get now?? i hear they are supposed to be less suseptable to breaking up than the cermaic ones. is this true or just marketing cr*p? lol
thanks Chris.
thanks Chris.
Without seeing them practically used I'd have to bet that the catalyst material will still go flying down the exhaust every now and then, but I don't know. 
Just my $.02
Dave
Joined: Jun 2004
Posts: 1,501
Likes: 7
From: Ft. Irwin, California (But Virginia is home)
Originally Posted by chuntington101
what are your impressions on the matalic cats that you can get now?? i hear they are supposed to be less suseptable to breaking up than the cermaic ones. is this true or just marketing cr*p? lol
thanks Chris.
thanks Chris.