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What options do I have for getting rid of the cat?


duckalot

Member
Joined
May 28, 2020
Messages
30
Location
North Missouri
I haven't done any research yet but my Cat seems to be shot, making a horrible rattling sound in side and the muffler needs replaced too.
What options do I have for getting rid of the cat? Inspections or emissions in my area are not a problem.
Thanks
 

Chris

Administrator
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Sep 28, 2015
Messages
50,813
Location
Florence, AZ
Do you live in a state with emissions or inspections?

If not, you can remove the cat and tune it out via HPTuners MPVI2 software.

This is what I did on my TJ. No check engine lights, no issues.

However, I live in a county with no emissions or inspections.
 

Wildman

Over Analizer Extraordinaire...............
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Dec 12, 2015
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In the hills of WA
It has always been my understanding that you TECHNICALLY are not allowed to tamper with any emissions equipment. Just like by federal regulations you have to use the same or new year engine if you want to do a engine swap. I'm no EPA lawyer and I am sure no one is going to run around crawling under your rig to see if you have all your emissions equipment unless you live somewhere that requires it.

I guess I would ask what advantage is there in removing the cat? Or any other emissions equipment? I know in the 70's and 80's you wanted/needed to because it affected performance but was under the impression that wasn't the case anymore.
 
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jodomcfrodo

Antagonist and Dick
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Feb 24, 2016
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Evanston, IL, United States
Take it off, jam a stick through it, bolt it back up. That’s how some high school friends used to fix their broken cats and pass visual inspection.

If that idea doesn’t appeal to you, which it probably shouldn’t, I’m fairly sure you can just remove the third cat and put a straight piece in without any issues. I’ve considered doing that to get a little more sound, but I haven’t done it yet.
 

Jerry Bransford

TJ Guru Moderator
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Nov 9, 2015
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Escondido California
1990 Clean Air Act extended the anti-tampering provisions to individuals
I just researched that and you are correct. BUT if you live in states without smog tests, it's a moot point. The Feds don't have roving teams of FBI agents looking for missing or defective catalytic converters.
 
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WallyWest

TJ Enthusiast
Joined
Nov 6, 2019
Messages
515
Location
PA
I just researched that and you are correct. BUT if you live in states without smog tests, it's a moot point. The Feds don't have roving teams of FBI agents looking for missing or defective catalytic converters.
They do exactly that for commercial trucks. And I have not seen it myself but have heard from several people in the hot rod, custom builder, scene that feds occasionally show up at their events checking exhausts.
 
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