That’s funny, Californian allowing you to remove factory installed/Californian mandated emission equipment!
Pre-cats, Y pipe
Thread Starter
Pro
Joined: Nov 1999
Posts: 659
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From: Woodland Ca
Pre-cats, Y pipe
I seemed to have read somewhere here on the Forum that, here in Calif. that it was legal to replace the pre-cats with a straight y pipe and larger main cat.
Has anyone had any experience or know of this?
Thanks!
Has anyone had any experience or know of this?
Thanks!
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
I'm not filmiliar with Calif. laws. I know here that there is not a law again removing the precats, but a huge fine if the Cat is removed or hollowed.
I have had a muffler shop remove the precats, but wouldn't touch the main cat.
I have had a muffler shop remove the precats, but wouldn't touch the main cat.
Pro
Joined: Apr 2005
Posts: 590
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From: Boynton Beach, FL
California doesn't allow you to remove any smog equipment. Most Smog techs don't know Corvettes so as long as they look under car and see one cat and car passes sniffer test, no problem. Pre cats don't do anything for California smog anyway. The are there to pass cold start emissions requirement, not a problem in LaLa land. 
Larry
Larry
Le Mans Master
Joined: Jun 2006
Posts: 5,642
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From: One day you're a Comet...the next day you're dust... Arkansas
Probably just someones' opinion. That someone will not be there when you go to pay your fine. The California statute is public record. My suggestion would be to read it. I was a certified state inspector years ago. If you can quote the statute, and are within it, they will back off.
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Has anyone had any experience or know of this?
You could get around a strict visual check by cutting the pre-cat shells from the stock exhaust and having them welded around a nice mandrel-bent front Y; then a hi-flow 3-stage main cat would get you past the sniffer.
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From: Jennings LA
Pro
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From: Boynton Beach, FL
Larry