Cat gutting - stupid questions
Thread Starter
Instructor
Joined: Aug 2003
Posts: 151
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From: Marietta GA
Cat gutting - stupid questions
Sorry, but my search feature is down.
Can I assume that when you gut your cats to reduce back pressure you are also rendering the car non-street legal? Georgia has yearly emissions tests.
Any feelings for how many miles of normal (non-track) driving it takes to get the cats to a point where they are abnormally restrictive?
Thanks
Can I assume that when you gut your cats to reduce back pressure you are also rendering the car non-street legal? Georgia has yearly emissions tests.
Any feelings for how many miles of normal (non-track) driving it takes to get the cats to a point where they are abnormally restrictive?
Thanks
Team Owner
Joined: Sep 2003
Posts: 25,295
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From: I'm the walkin dude I can see all of the world...
St. Jude Donor '03
Re: Cat gutting - stupid questions (95VROOM)
Hmm I dont listen to all the talk about back pressure. Im sure others with flame me for that. If you gut your cats you will not pass state inspection.
Do this:
Get bolt-on straight pipes inplace of the cats. Be sure to include the O2 bung. Cost 100$ at the most. Then when inspection comes put the cats back on. This is a good mod. The cats were really holding back my '92. Probably the easiest/cheapest thing I ever did to it.
:chevy
Do this:
Get bolt-on straight pipes inplace of the cats. Be sure to include the O2 bung. Cost 100$ at the most. Then when inspection comes put the cats back on. This is a good mod. The cats were really holding back my '92. Probably the easiest/cheapest thing I ever did to it.
:chevy
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
Re: Cat gutting - stupid questions (VictorRussell'92)
If you gut your cats you will not pass state inspection.
You can easily pass emissions tests if the car is in proper running order. You "might" not pass a visual if they actually crawl under the car to look, but if you retain the stock bodies of the cats and just put a piece of straight pipe inside of them nobody will ever know. ;)
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Re: Cat gutting - stupid questions (scorp508)
You'll know when your cats are going bad! Yeah, I've taken a cat off and knocked out the material, put it back on and never had a problem with passing emissions :D just keep it well tuned and :steering:
Pro
Joined: Mar 2002
Posts: 732
Likes: 138
From: Allen (DFW) Texas
Re: Cat gutting - stupid questions (95VROOM)
Some of the posted replies may be incorrect depending on the year of your car and the method your state uses for testing. I'm assuming from your alias that yours is a 95, which if memory serves was still OBD I. Mine is a 96 and is OBD II, has an O2 sensor ahead of the cat and one behind, on each side, and if the cats are gutted you have to use a gadget to bypass those behind the cats or the computer will set codes, the SES light will stay on, and at least in Texas the car won't pass the emissions test. On OBD II cars, Texas doesn't use the "sniffer" just an electronic scan so even a finely tuned car won't pass if the sensors aren't all working. So make sure you know what kind of test your state does - it gets expensive if you end up having to replace those cats to renew your tags, and don't ask how I know that 'cause the memory is still painful.
