Catalytic converter replacement suggestions?

Have you since needed to switch to CARB EO cats for CO testing?

No I have not. I'm not sure if Colorado is now as strict as California is when it comes to cats and smog. If I remember correctly, I put those on just before getting checked and it passed. In December 2022, I was required to smog again and it passed.

The Smogites, plugged in, then put her on the dyno wheel, then drove it to the exit where the payment lady was all excited... "Wonderful you passed !"

I laughed because I've never had somebody get that excited over a smog test.... I wasn't surprised it passed, as I keep the TJ maintained.

Also, I never saw anybody with a mirror or physically go under to look at the exhaust system.

Ray
 
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No I have not. I'm not sure if Colorado is now as strict as California is when it comes to cats and smog. If I remember correctly, I put those on just before getting checked and it passed. In December 2022, I was required to smog again and it passed.

The Smogites, plugged in, then put her on the dyno wheel, then drove it to the exit where the payment lady was all excited... "Wonderful you passed !"

I laughed because I've never had somebody get that excited over a smog test.... I wasn't surprised it passed, as I keep the TJ maintained.

Also, I never saw anybody with a mirror or physically go under to look at the exhaust system.

Ray

Hi Ray, how are the Evan Fischer cats holding up?
 
Just read this thread and have a couple questions:

Is everyone still happy with their Flowmaster cat setup?

Are TJ and LJ the same part for this?

https://www.holley.com/products/exhaust/catalytic_converter/49_state/direct-fit/parts/2049170

I only use the pre-cats, but they have been holding up to the turbo. I like that it's mandrel bent and stainless.

I chose "Unlimited" as the application, and Holley's website says the kit fits. The reviews also indicate that it fits an LJ.

Application

Screen Shot 2024-05-20 at 5.09.07 PM.png


Reviews by LJ owners (first and third review)

Screen Shot 2024-05-20 at 5.09.34 PM.png
 
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I have Flowmaster cats and NTK sensors ready to go in this week. I've never swapped cats but it seems pretty straightforward. I ordered from Amazon but shipped from Holley. Not a lot of packaging and this is on the bottom flange in the picture. I'm not exactly sure if this will create an issue or not.

IMG_0622.JPG
 
I have Flowmaster cats and NTK sensors ready to go in this week. I've never swapped cats but it seems pretty straightforward. I ordered from Amazon but shipped from Holley. Not a lot of packaging and this is on the bottom flange in the picture. I'm not exactly sure if this will create an issue or not.

View attachment 530191

I wouldn't chance it...you don't want an engine code popping due to air hitting the B2 sensor. Folks like myself have had to retighten their flange-mount fasteners for that reason.

Sorry man, I've been there with two damaged manifolds shipped bad from JBA and it wasn't a good time "proving" the problem to multiple people through emails and phone calls. I say this all in hopes that your experience will be much less annoying.
 
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I wouldn't chance it...you don't want an engine code popping due to air hitting the B2 sensor. Folks like myself have had to retighten their flange-mount fasteners for that reason.

Sorry man, I've been there with two damaged manifolds shipped bad from JBA and it wasn't a good time "proving" the problem to multiple people through emails and phone calls. I say this all in hopes that your experience will be much less annoying.

Damn. I was hoping to get that thing out on the beach next weekend. Thanks for the reply.