Catalytic Converters Issue
Thread Starter
Heel & Toe
Joined: Mar 2013
Posts: 24
Likes: 0
From: Lexington
Catalytic Converters Issue
My car is making unusual sounds and the mechanic I use says my catalytic converter has gone bad. Will this do harm to my motor if not replaced? How complicated is this to replace? Thanks, this forum has helped me a lot over the years! Thanks for any response. R Woolley
Melting Slicks
Joined: Jan 2014
Posts: 2,192
Likes: 381
From: Lunenburg MA
A bad CC can damage an engine if it's clogged. It's generally a PITA as are most exhaust parts. Take it to an exhaust shop for an estimate unless you're comfortable working on exhaust systems.
Instructor
Joined: May 2019
Posts: 148
Likes: 35
From: Virginia
My 87 had 2 cats in the Y pipe coming off the manifolds and one mid way back in the exhaust line.... which one is bad? If its the single mid way in your exhaust, take it to a exhaust shop and have it replaced with a hi flow cat. I did mine and had the 2 in the front Y pipe removed, sounds much better and got rid of the 33 year old cats....
Last edited by vyper202; Aug 7, 2020 at 12:11 AM.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
What year Vette?
If it has the three cats, have the front Y replaced with a cat-less unit and the main cat replaced with a hi-flow unit for a nice HP gain.
I used a Random Tec cat on my prior '88 with great results.
If it has the three cats, have the front Y replaced with a cat-less unit and the main cat replaced with a hi-flow unit for a nice HP gain.
I used a Random Tec cat on my prior '88 with great results.
Team Owner
Joined: May 2000
Posts: 53,774
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From: Plantation Florida USAF(Retired) 1966-1990
U.S. Air Force
St. Jude Donor '05 thru '26
NCM Sinkhole Donor
Any muffler will check you cats at no charge, if they find them bad ask for estimate, and ask if I bring you set how much.
Then go to E-bay, and see what they have in OEM which would be lot cheaper then muffler will charge you, and they would buy aftermarket, which sometimes aren't the best choice.
Then go to E-bay, and see what they have in OEM which would be lot cheaper then muffler will charge you, and they would buy aftermarket, which sometimes aren't the best choice.
Race Director
Joined: Feb 2002
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From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
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St. Jude Donor '16
Generally with bad cats you get a low hot exhaust low and low power or lack of RPMs.
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Melting Slicks
Joined: Jan 2009
Posts: 3,482
Likes: 196
From: folsom california
Go online and look for "direct replacement" or "direct fit", assuming your cats are oem, the old ones should unbolt and the new ones bolt right back in in their place. The costs arise when trying to use an "universal" style cat; these will require pipe fabrication and welding.