It would take at least two driving cycles to make the MIL come on wouldn’t it?
I don’t think replacing the catalytic converter with pipe would make it louder. The catalytic converter is not a muffler. The resonator and muffler are still there.
The cat is a pretty good muffler. Removed the muffler on my 1975 Starfire (like a Chevy Monza) with a V6 but left the car in place. Gave the car a nice rumbly sound without being obnoxious. Actually took it to a free emissions check run by the state police. When I started it up after the tailpipe test they held me for a moment and looked for the muffler. None found, they had me rev it up… shrugged and let me go.
The matrix inside modern cats break up the sound waves fairly effectively. With a turbo car and a cat only, the car is actually not obnoxiously loud. A NA car with cat only would be loud, but much louder it the car was gone. In the Mustang community, you get to hear most of those variations at car shows.
No. Should be immediate.
YouTuber site sells stripped car parts. He says sst headers are nice but he prefers cats to scrap? Sst headers for vettes are $1500? Cats are less? Whatever.
Stainless long tube headers are in the $1000 to $1500 range for most any V8 car.
Back in the 1975-85 time frame I replaced lots of catalytic converters with the common widely available “converter test pipes”. The cars were not noticeably louder with the cat replaced by a pipe.
However given the sound design in today’s exhaust systems is far different than it was years ago, I’m not saying a current model car won’t be louder with the cat removed. You’ll need to try it.
As for emissions, if you do remove your cat, you should be able to fake out the emissions by using a spark plug non-fouler in place of the downstream O2 sensor. You may need to get creative in how you do it for any given model car, but it will work. And do understand the legal risks of doing it.
A v8 with dual exh usually sounds pretty good. Lots of people buy nice stuff for cars they like
Why has no one questioned why one would want to do this? All issues of sound and federal penalties aside, removing the cat means that the car will be spewing out more pollution than necessary, and everyone in the immediate vicinity will be forced to breath more unclean air. Preventing that level of crud in the air is why cars have cats to begin with. It is selfish to think that simply removing it is purely a personal decision. We all suffer.
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Depends on where the OP lives. Many cars sold in South America come with Catalytic converters, but they are NOT required. You can remove it without any penality.
Hey, that looks just like my commute down 95 in the morning!
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My point has nothing to do with legality. The catalytic converter reduces pollutants that are released into the air. Do you disagree with that statement?
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All cars and light trucks built and sold in the United States after January 1, 1996 were required to be OBD II equipped. In general, this means all 1996 model year cars and light trucks are compliant, even if built in late 1995.
Tester
1996 F-150 is OBD II but has no catalyist monitoring. Thinking it must be a 1995 product.
This is why you never believe a single word this guy types.
https://www.justanswer.com/ford/20mr4-oxygen-sensors-1996-ford-f-150-5-0.html
Tester
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Never said I didn’t. Many people have different reasons to remove catalytic converter. One is less restrictive exhaust and this better gas mileage. You can also run leaded gas (which many countries still have). I wouldn’t remove the cat.
Hi Jdmere:
While I don’t disagree, I do view the concern differently.
Yes, catalytic converters do help reduce hydrocarbons, but they don’t reduce carbon dioxide or nitrious oxide. Meaning, they help, but they’re only part of the solution to reduce emissions. There have been many changes over the years in the engine and engine controls that play a significant role in reducing emissions.
If we’re going to be concerned about a handful of drivers removing their cat, shouldn’t we be more concerned with the increase in vehicles on the roads over the years, and the increase in miles driven?
By most estimates, catalytic converters fitted inside the exhaust pipe of a gasoline-operated car convert over 90% of hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) from the engine into less harmful carbon dioxide (CO2), nitrogen and water vapour.
Tester
OK. I’ll agree the info out there differs on which pollutants a cat reduces. I saw the site that you cut-n-pasted from.
Even if that site is correct, is it fair to be concerned with a handful of cars emitting more than than their car was built to emit, and not to be concerned with the large increase in vehicle traffic?
The well documented latter contributes far more than the former.
I was involved with exhaust emission research, and the statement I cited is correct.
That’s usually caused by owners who ignore the CEL, or vehicle that hasn’t been maintained.
Or those who tamper with emission control devices.
But now, that’s because you’ve got people involved.
And some aren’t the brightest bulb on the Christmas tree.
Tester
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