Its completely LEGAL to not run a cat here in illinois if your car is over 10 years old. Anything newer than that has to pass emisions though. But most of our jeeps fall into the do whatever you want to the exhaust catagory. Just remember cops still dont like cars without a muffler.

 

what hes saying is that its federal law so its illegal everywhere, but gambling is federally illegal but somehow legal in vegas

 

just puttin my 2 cents in, btw it sounds awesome

 

Will straight piping it after the cat give alittle more power?

 

Top end, maybe. Low end, no.

 

i put a glasspack on mine and it rattled on the shackle s i chopped it after the muffler but i think its louder in the car than outside:/

 

This was true... in 1985.

Anything after 75 was mandated to have a cat from the factory, and if your rig had a cat OEM no amount of time will delete that fact. It's a Federal emissions mandate that cannot be superceded by state law.

 

yup

 

By far the cheapest modification I've done.

-On the 97ZJ, it sounds like a full custom job.

-On the 95XJ, it's obvious there's no muffler (still sounds good though).

--It's a redneck version of 'cool' lol

 

If your veichle came with a cat you must run one, no ifs ands or buts. You cannot just remove it legally even if your jeep is ten yrs old. Where some of you guys get your info is beyond most of us cause your WRONG AGAIN. Please wipe your hard drive and reinstall your operating system.

 

having a cat will reduce the raspy note of the engine. Having a resonator style muffler also helps.

 

Might not wanna go straight pipe. Mufflers are there for a reason and there's so many out there with different decible readings, a good muffler shop will install one with the sound you are looking for. Back pressure has a whole lot to do with the performance of your motor, take it away and you may experience different torque and HP readings at different RPMs than before.

 

it just really depends on how much you want to spend on your exhaust setup. Having a cat is a federal law where a muffler im not sure if it varries from state to state. I just bought a zj that has the 5.2 v8, and of course theres a big freaking hole in the exhaust piping right after the cat. Its very loud and deep. But having all the exhaust exiting directly under my cab doesnt sound great.
My last xj had kinda the same issue before I had the exhaust fixed, but in this case the exhaust leaked up into the cab and made people sick. So if you plan on dumping ur exhaust under the cab make sure the fumes dont leak back up into your rig.

 

You bring up a good point BigRed. Here in Pa the exhaust needs to exit beyond the passenger cabin... on an XJ that would be considered the rear bumper as it's not seperated by a trunk and bulkhead.

 

very true... i had mine right after the cat and it was so annoying so i went to my grandpa's shop and he helped me weld a outlet on the side right in front of my rearpassenger tire. it sounds way better inside the cab and out