When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Had a question about what type of exhaust system I wanted to run in my jeep. Planned on running straight pipe to the muffler (flow master 44). Don't want it to drone and sound ricey tho. Most XJs I've heard with no cat and a flow master don't sound too bad. I hope this doesn't get taken down because I do know that running no cat converter is illegal but I'll be honest with you all its not really enforced too strictly in East Tennessee and tons of jeeps run without one. Will it make a big difference? And what is your alls' set ups?
[QUOTE="Johnnybanks;3225748"]Had a question about what type of exhaust system I wanted to run in my jeep. Planned on running straight pipe to the muffler (flow master 44). Don't want it to drone and sound ricey tho. Most XJs I've heard with no cat and a flow master don't sound too bad. I hope this doesn't get taken down because I do know that running no cat converter is illegal but I'll be honest with you all its not really enforced too strictly in East Tennessee and tons of jeeps around here run without one. Will it make a big difference? And what is your alls' set ups?
I hope this doesn't get taken down because I do know that running no cat converter is illegal but I'll be honest with you all its not really enforced too strictly in East Tennessee and tons of jeeps run without one.
It won't get taken down just because it's illegal, but also because it's against forum rules.
Posting blatant illegal acts, no matter how insignificant you may think they are, openly online...well that's just another level of special.
As far as the muffler part of the question...some really like the sound of the 44, some hate it. It's all opinion I suppose. I like the 60 when given throttle, at idle it's too quiet. Many have opted for a Thrush welded, similar to FM but much less money. I'm still running the OEM replacement crap because I haven't found a muffler for the 4.0 that I really like yet.
Just a heads up no cat you will have a check engine light for life and will lose a few mpg also.Even if your state don't smog test its a fed law and caught with out one they can impound your jeep on the spot.A high flow cat is cheap and will keep the jeep happy.Most on here like http://performance-curve.com/jeepkits.aspx and he has cats also.
It is a federal law, and it ensures cleaner air for all of us. It is NOT a performance restriction, and even a really nice one does NOT have to be expensive (see www.performance-curve.com).
This is my system:
Thorley header, spun stainless cat from Performance Curve, stainless Flowmaster Super 50 Delta Flow, and stainless 2.25" pipe.
So basically the way to go is to get an aftermarket catalytic converter with the muffler? I know a past XJ I had cat's stopped up and it was running like crap. Also know of someone that has none and he has 250k on his XJ? You guys recommend the magnaflow cat?
I bought a magnaflow off of amazon, I also replaced everything from the up pipe to the tail pipe. Cat, O2 sensor, Muffler, hangers had to make a trip or two to autozone for some random stuff and just used clamps. All in for less than $350.
To believe that a "high flow" cat is a thing that would actually provide any benefit is foolish. For an XJ with a 4.0, you'd have to try quite hard to build it to the point that even a factory cat would be the primary restriction in flow. Just get a quality cat (which probably IS a "high-flow" for anyone who insists on caring about "high-flow"), and don't pay any more than you have to for it.
$70 for a cat from PF.
$150 for a Dynomax cat-back ($100ish if bought during rebate season).
Fantastic bang-for-buck.
Last edited by mschi772; Mar 13, 2016 at 04:10 PM.
Magnaflow cat is a waste of money. There's nothing it has (other than Magnaflow's name) that a MUCH cheaper cat from Performance Curve doesn't have. You're just paying for a name.
Furthermore, to believe that a "high flow" cat is a thing that would actually provide any benefit is foolish. For an XJ with a 4.0, you'd have to try quite hard to build it to the point that even a factory cat would be the primary restriction in flow. Just get a quality cat (which probably IS a "high-flow" for anyone who insists on caring about "high-flow"), and don't pay any more than you have to for it.
$70 for a cat from PF.
$150 for a Dynomax cat-back ($100ish if bought during rebate season).
Fantastic bang-for-buck.
The magnaflow cat I bought is on Amazon for about $72, so it is right in line with what you posted as a more economical option. Then using amazon prime it is on the porch in two days no shipping. I was suggesting an option not a magnaflow sales rep.
This thread was about to go away. But since you are all telling him to keep the cat it stays.
I did remove the posts talking up removing the cat with gains.
If you removed a cat and gained something you had other issues.
Vehicles are tuned to run with a cat. Leave a cat on. Period.
The magnaflow cat I bought is on Amazon for about $72, so it is right in line with what you posted as a more economical option. Then using amazon prime it is on the porch in two days no shipping. I was suggesting an option not a magnaflow sales rep.
Fair enough. I've never seen a "brand name" cat that wasn't overpriced, but I also haven't deliberately shopped for them either--only know the prices I happen to have seen in passing, and all I've seen have been prices well over $100.
Exhaust System Questions
