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Long arm suspension and catalytic converters

EvaB99XJ

NAXJA Forum User
NAXJA Member
Location
Ridgecrest, CA
Hi - I’m making plans to put a long arm lift kit (6 inches or more) on my XJ. Since I live in California I cannot touch the exhaust from the converter forward if I want it to pass smog.

I’ve read the installation instructions for the iron rock and another kit and they require exhaust mods ahead of the converter for the long arm kits.

My question (I did a search and found nothing) is whether all long arm kits require exhaust mods ahead of the converter? I’ll run leaf springs if I have to, but I’d rather not if there is an alternative.

Thanks!
 
please provide a link to the instructions that indicate exhaust modification so we can analyze what the modification need be.

the cross member is different, so I assume that is the change, as the stock exhaust is attached to the stock crossmember. Perhaps the only change is to how it mounts? if so that would likely not trigger a smog test fail.

Did you contact the makers? they may have an answer as they probably sell a good deal of these kits to folks stuck in Commifornia.
 
As others have said, what year XJ? I have a 2000 XJ with California emissions and I didn't have to modify anything at all for the long arm kit I put on. Also, where did you get the idea that you can not touch anything from the converter forward? By the letter of the law I believe the converter just has to be the same distance it was originally from the exhaust manifold. I have never heard of anyone actually checking that, - they usually just check you have a CA legal cat and that it sniffs fine (if you are pre-ODB2) or if you are ODB2 they just plug in to check everything.
 
The OP is correct regarding the letter of the law regarding emissions. (Speaking as one who used to work for Hooker Headers and the development of new products.) Any exhaust modifications before the cat are required to have a CARB E.O. tag. After the cat you can do most anything you like as long you aren't too loud.

Now, that said, a change such as an exhaust hanger or the addition of a dent in a pipe is not likely to be an issue.

The question really comes down to what modications are required? Get the details on that and you can get better answers.
 
Looking at the instructions where it says to cut exhaust by the tcase, you should be able to cut the exhaust after the cat. Looks like the re-route is after crossmember which wouldn’t effect the cat as far as I can tell, from the instructions and illustrations you posted anyway.


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In my opinion, completely disregard their usage of the word "cut"; they more correctly should have said in step 65 to "remove" the exhaust from the Cat rearward. Under the "Before you begin" section, they list a custom exhaust or their PN 13888, which is only Cat-Back components. Just to note, this modification is only required for the rear 4-link; a front 3/4 link will not require any modification. IRO is run by a bunch of fellow Jeepers, not some big business; I'm sure if you call and ask they will answer all of your questions.
 
In my opinion, completely disregard their usage of the word "cut"; they more correctly should have said in step 65 to "remove" the exhaust from the Cat rearward. Under the "Before you begin" section, they list a custom exhaust or their PN 13888, which is only Cat-Back components. Just to note, this modification is only required for the rear 4-link; a front 3/4 link will not require any modification. IRO is run by a bunch of fellow Jeepers, not some big business; I'm sure if you call and ask they will answer all of your questions.


I have noted many installation instructions to be horribly written, be it suspension, bumpers etc.. Horrible wording, horrible diagrams or lack of them. They just plan often suck. Reading the linked instructions was a painful experience.
Vendors need to step up their game, and no a YouTube video link does not make up fkr the lack of good written instructions.

I have passed on buying some products because of the low quality of the instructions. Bumpers are really bad, you go to the manufacture website to see how a bumper mounts are like, not a single image of the mount side of the bumper, but ten images of the outside of the bumper, you open the pdf link to the instructions and no image, you email the maker (ARB, SmittyBilt, I am talking to you) and they offer no help as to what the mounting is like. They appear to want you to buy the product to find out. ugh!
 
I have noted many installation instructions to be horribly written, be it suspension, bumpers etc.. Horrible wording, horrible diagrams or lack of them. They just plan often suck. Reading the linked instructions was a painful experience.
Vendors need to step up their game, and no a YouTube video link does not make up fkr the lack of good written instructions.

I have passed on buying some products because of the low quality of the instructions. Bumpers are really bad, you go to the manufacture website to see how a bumper mounts are like, not a single image of the mount side of the bumper, but ten images of the outside of the bumper, you open the pdf link to the instructions and no image, you email the maker (ARB, SmittyBilt, I am talking to you) and they offer no help as to what the mounting is like. They appear to want you to buy the product to find out. ugh!

Where is the "like" button.

This has been a pet peeve of mine for decades. The worst was even while working for Hooker I could not get it through to marketing that they needed to do something about this. As far as they are concerned there is no money in it.

OTOH, my accolades to Brown Dog. The instructions that came with their motor mounts/block plates were excellent. I could tell that they have been paying attention and collecting information about the variety of engine blocks and the various ways customers have found to screw up on the install. Of all the instuctions I have ever dealt with Brown Dog's has been the most impressively well written and illustrated.
 
In my opinion, completely disregard their usage of the word "cut"; they more correctly should have said in step 65 to "remove" the exhaust from the Cat rearward. Under the "Before you begin" section, they list a custom exhaust or their PN 13888, which is only Cat-Back components. Just to note, this modification is only required for the rear 4-link; a front 3/4 link will not require any modification. IRO is run by a bunch of fellow Jeepers, not some big business; I'm sure if you call and ask they will answer all of your questions.


Yes, calling the vendor is probably the best idea.

I’m in the early stages of planning which kit to go with and my first thought was to pick the brains here since y’all have been there and done that.

Thanks for the help 🙂
 
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