Novak Conversions Jeep Wrangler TJ engine mounts

2004 Rubicon Exhaust

But they cause a host of problems and the cause of many others along with codes not related to th o2 system.

I might just be lucky with it, but I've only had one "catalytic system" code thrown over the years, and that was due to a clogged fuel filter on a car that had sat for about 5-6 months. Even my 300K mile Civic has never thrown a catalytic system code, or any other code for that matter, so I'm not really sure what host of problems they cause. Care to elaborate?
 
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I can't smell the difference between a cat vs non-cat vehicle when tuned correctly, but I can smell one running non-pump gas. ;)

Your nose must be burnt out 🤣 my MR2 is way stank compared to a Camry with the same engine
 
When I was stationed in Norfolk….the dang inspector always re-aimed my left headlight and pointed it into the trees on the right side of the road. Why?

Must have been this guy. :unsure:

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I’ve driven the jeep around for a few weeks now and have noticed a huge improvement when driving around the city, but still get some “blow back” when on the highway on a sustained hill climb slammed in third.

I get a hit with a pretty bad exhaust smell when in this situation. I am thinking about doing an exhaust manifold gasket or the manifolds and gasket (they aren’t super pricey $200) in recommendations?

Is it worth replacing the manifolds with the same manufacturer of the gasket to ensure fitment?

Any recommendations on gasket manufacturers?
 
Anyone knows if this older catless down pipe (out from a TJ imported from japan) will fit my 2005 TJ Rubicon?.
I want to remove the 2 cats and 2 O2 sensors after and was thinking to use this downpipe, cut it just before the O2 sensor bung and weld it to my OEM exhaust pipe, before the third cat converter. (I know i'll have to deactivate the 2 O2 sensors with HP Tuners)

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Anyone knows if this older catless down pipe (out from a TJ imported from japan) will fit my 2005 TJ Rubicon?.
I want to remove the 2 cats and 2 O2 sensors after and was thinking to use this downpipe, cut it just before the O2 sensor bung and weld it to my OEM exhaust pipe, before the third cat converter. (I know i'll have to deactivate the 2 O2 sensors with HP Tuners)

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Yes, but why? Have your mini-cats gone bad? They're not robbing you of significant power if they haven't failed. Also, you can just have O2 bungs welded in to the downpipes and keep the existing sensors rather than disable them in HPTuners. Perhaps space them back a bit. Up to you on that. And just use a plug on that downstream bung and cut below it if you can. You might want to pop a wideband O2 sensor in there later.
 
Yes, but why? Have your mini-cats gone bad? They're not robbing you of significant power if they haven't failed. Also, you can just have O2 bungs welded in to the downpipes and keep the existing sensors rather than disable them in HPTuners. Perhaps space them back a bit. Up to you on that. And just use a plug on that downstream bung and cut below it if you can. You might want to pop a wideband O2 sensor in there later.

Yes, i think they are gone bad and here in Chile can´t find a new catted downpipe (TJ's aren´t common), so i have to import it and will cost more than USD 600.
Also, i have to re tight the bolts very often because they go loose, and with the precats it's very difficult.
 
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Novak Conversions Jeep Wrangler TJ engine mounts