wanting to remove catalytic converters
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Joined: Apr 2005
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From: brandon florida
wanting to remove catalytic converters
Can this be one without check engine light coming on? Have the shield rattle coming from under the car. What is the best free flow exhauust to put on? Thanks
Melting Slicks
Joined: Feb 2008
Posts: 3,286
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From: Palm Beach
I have it and love it. Everything else is a compromise.
Le Mans Master
Joined: May 1999
Posts: 6,520
Likes: 1,306
From: Windermere FL
Getting the dreaded SES is hit or miss. I never got it with a gutted cat and hooker headers in my 90. I ran with it like that for years. But then I finally got around to converting it to true dual exhausts and while I was at it they welded in some hi flow cats. Cost me about $500 otd. All the air pump crapola was long gone but the new technology does not need it. Glad I made the switch. No more black sot on the rear bumper. But I do miss belching out a nice cloud of smoke when passing those friggin bicyclists that insist on blocking roads around here rather than sticking to bicycle lanes.
Team Owner
Joined: Dec 1999
Posts: 34,873
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
There won't be any SES light if you remove the main cat. But do you live where emissions testing is required, you will certainly fail.
And if you try going to a muffler shop to simply have the cat removed, the chances are good that they will refuse. There is a 5-figure fine if the feds catch a shop removing a working cat from a car. Same if they remove a bad cat and it's not replaced.
Some shops will install an "off-road" exhaust if you take the car to them without an exhaust system (nothing past the manifolds) and no plates on the car. But you still have to put the O2 sensor back to keep the ECM from throwing a code and not going into closed loop when it should.
Edit; Your profile says you have a '98 C5. You may want to ask this in the C5 Tech section. Butlike that LT1 C4 cats, C5 OEM cats actually flow very well and there is nothing to be really gained by removing them. For a good cat back, look at Corsa, Borla, or Magnaflo.
And if you try going to a muffler shop to simply have the cat removed, the chances are good that they will refuse. There is a 5-figure fine if the feds catch a shop removing a working cat from a car. Same if they remove a bad cat and it's not replaced.
Some shops will install an "off-road" exhaust if you take the car to them without an exhaust system (nothing past the manifolds) and no plates on the car. But you still have to put the O2 sensor back to keep the ECM from throwing a code and not going into closed loop when it should.
Edit; Your profile says you have a '98 C5. You may want to ask this in the C5 Tech section. Butlike that LT1 C4 cats, C5 OEM cats actually flow very well and there is nothing to be really gained by removing them. For a good cat back, look at Corsa, Borla, or Magnaflo.
Last edited by c4cruiser; Oct 23, 2009 at 06:03 PM.
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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Unless you like a louder than H&LL exhaust, I don't agree with your plan. Most drivers require some muffling to keep things reasonable. And, the C4 cabin is really susceptible to resonance. As such, noise is amplified in our cars.
CATS -- as with mufflers -- provide noise suppression. If you want a free-flowing exhaust, consider dual cats (up front) and no mufflers. Compared to the alternative (no cats WITH mufflers), you're much better off in terms of smell, compliance, and overall refinement. Sound-wise, the result can end up the same.
JMO.
CATS -- as with mufflers -- provide noise suppression. If you want a free-flowing exhaust, consider dual cats (up front) and no mufflers. Compared to the alternative (no cats WITH mufflers), you're much better off in terms of smell, compliance, and overall refinement. Sound-wise, the result can end up the same.
JMO.
