79vette catalytic converter
Thread Starter
Intermediate
Joined: Jul 2016
Posts: 35
Likes: 2
From: Charlotte NC
79vette catalytic converter
My car is going to the shop to have the engine mounts and catalytic converter hangar support bracket replaced. I was thinking of having the converter removed. Can I replace it with a straight pipe, and will this take some back pressure of the all ready loaded down 350 ?
Thank you
7ron9
Thank you
7ron9
Intermediate
Joined: Jul 2011
Posts: 39
Likes: 5
From: Cleveland, OH
Definitely! That converter is 37 years old and not functional anyway. I just replaced the exhaust on my 79 and left the converter off. It was plugged, internally corroded, and was really degrading the performance of the SBC. BTW... my mufflers were not helping matters either.
I went with a 2.5" straight dual exhaust (essentially a 1974 system) and couldn't be happier. The improvement in the motor and overall performance was striking. I wish I had done it sooner.
That said, removing the converter may leave you unable to sell/transfer title or pass emissions testing if NC requires such inspections. That varies by state, so it would be good to know beforehand.
I went with a 2.5" straight dual exhaust (essentially a 1974 system) and couldn't be happier. The improvement in the motor and overall performance was striking. I wish I had done it sooner.
That said, removing the converter may leave you unable to sell/transfer title or pass emissions testing if NC requires such inspections. That varies by state, so it would be good to know beforehand.
Thread Starter
Intermediate
Joined: Jul 2016
Posts: 35
Likes: 2
From: Charlotte NC
Converter
Definitely! That converter is 37 years old and not functional anyway. I just replaced the exhaust on my 79 and left the converter off. It was plugged, internally corroded, and was really degrading the performance of the SBC. BTW... my mufflers were not helping matters either.
I went with a 2.5" straight dual exhaust (essentially a 1974 system) and couldn't be happier. The improvement in the motor and overall performance was striking. I wish I had done it sooner.
That said, removing the converter may leave you unable to sell/transfer title or pass emissions testing if NC requires such inspections. That varies by state, so it would be good to know beforehand.
I went with a 2.5" straight dual exhaust (essentially a 1974 system) and couldn't be happier. The improvement in the motor and overall performance was striking. I wish I had done it sooner.
That said, removing the converter may leave you unable to sell/transfer title or pass emissions testing if NC requires such inspections. That varies by state, so it would be good to know beforehand.
Thank you. My car no longer needs to be inspected
I put stainless cans on about ten years ago and they are in great shape probably because exhaust gases never got there...they just blew out the intake manifold!Ron
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
Your shop may decline to remove the cat because it's against federal law. The fact that inspection is not required did not change the law about removing or disabling emissions equipment. Just an FYI.
Le Mans Master
Joined: Oct 2007
Posts: 7,451
Likes: 974
From: RI, Now Franklin/Nashville TN
Most states do not require emissions on 20-25 years old cars except CA and a very few others. Technically speaking it is against the law to remove the cat but on a car that no longer has to pass emissions, you may get by having the shop do it. If not, cut the cat off yourself and use a flexible pipe from Autozone to drive the car to the shop for a straight pipe or full 2.5 inch duals (which is the best option for performance). The emissions nonsense on older cars is pure idiocy since these cars are driven 1/10th of 1% of the time.
Last edited by jb78L-82; Sep 17, 2016 at 06:57 PM.
Le Mans Master
Joined: Oct 2005
Posts: 6,247
Likes: 471
From: Glen Allen, VA
you may have a hard time getting a shop to delete the catalytic converter, and you may also have a problem getting them to replace a single exhaust system, which your 79 came with, with a true dual exhaust system. It's technically illegal to to do. As stated above, it is definitely idiocy! Our old cars are not the problem the EPA needs to be going after!
Burning Brakes
Joined: Jul 2004
Posts: 1,192
Likes: 111
From: If your not the lead dog the view never changes Boise, Id
I had true dual exhaust put on my car after replacing the heads and putting headers on it, the shop that did the engine work took it to an exhaust shop to do the work. The exhaust shop would not put on an exhaust without cats so I payed an extra $150 per side for them to put on "high flow cats" after just under 3 thousand miles the right cat started rattling, sounds like a coffee can filled with rocks. I took the car to the exhaust shop that did the work. Without even stepping out of the office to hear it the owner says Cats are never warranteed because there is nothing in them that can be made wrong. He then started blaming everything from pump gas, no smog pump, maybe a bad tune or plug wire. That destroyed that cat. I told him the top end was just rebuilt and aside from the cat the car runs great, he says running great has nothing to do with the car being tuned. Listening to this guy you would believe these damn high flow cats are made out of wet paper and anything will destroy them.
Last edited by RockyL32; Sep 18, 2016 at 12:38 AM.
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Drifting
Joined: Apr 2004
Posts: 1,422
Likes: 127
From: Mequon WI
Emissions engineering prior to computer electronics all looked at recirculating exhaust gasses to reduce emissions. All failed misserably. This was also tried with commercial laundry dryers (more to recover heat than reduce emissions) and that was a disaster too. Those of us who went through the evolution of pollution controls during the 70's saw performance drop, fuel effeciency drop and questionable results of actual emissions reduction. If you are using more fuel to do the same work, how can you be eliminating waste?
Computer electronics and combustion engineering have lead to actual emissions reduction, increased economy and greatly improved performance. IMHO it is a waste of time and a false economy to try to salvage 40 year old technology that never really worked.
I know some people, EPA, CARB, ETC will disagree but I doubt there is any logic to their thinking. OPPS, does this rant now belong in the PRC section?
Computer electronics and combustion engineering have lead to actual emissions reduction, increased economy and greatly improved performance. IMHO it is a waste of time and a false economy to try to salvage 40 year old technology that never really worked.
I know some people, EPA, CARB, ETC will disagree but I doubt there is any logic to their thinking. OPPS, does this rant now belong in the PRC section?
Thread Starter
Intermediate
Joined: Jul 2016
Posts: 35
Likes: 2
From: Charlotte NC
Cat Overhaul
7ron9
Le Mans Master
Joined: Oct 2007
Posts: 7,451
Likes: 974
From: RI, Now Franklin/Nashville TN
Emissions engineering prior to computer electronics all looked at recirculating exhaust gasses to reduce emissions. All failed misserably. This was also tried with commercial laundry dryers (more to recover heat than reduce emissions) and that was a disaster too. Those of us who went through the evolution of pollution controls during the 70's saw performance drop, fuel effeciency drop and questionable results of actual emissions reduction. If you are using more fuel to do the same work, how can you be eliminating waste?
Computer electronics and combustion engineering have lead to actual emissions reduction, increased economy and greatly improved performance. IMHO it is a waste of time and a false economy to try to salvage 40 year old technology that never really worked.
I know some people, EPA, CARB, ETC will disagree but I doubt there is any logic to their thinking. OPPS, does this rant now belong in the PRC section?
Computer electronics and combustion engineering have lead to actual emissions reduction, increased economy and greatly improved performance. IMHO it is a waste of time and a false economy to try to salvage 40 year old technology that never really worked.
I know some people, EPA, CARB, ETC will disagree but I doubt there is any logic to their thinking. OPPS, does this rant now belong in the PRC section?
Just buy a complete 2.5 true dual exhaust with Magnaflow mufflers from a vendor like Corvette Central and do it yourself, if you cam! Eliminates dealing with the policies, rules, and regulations from the **** EPA.
Last edited by jb78L-82; Sep 18, 2016 at 01:53 PM.