no muffler= no good?

[ridin44s]

i am installing my 2" exhaust this weekend on the yj with a 258 and was wondering if just running a cat can do any damage to the engine. if i run straight pipes is that to bad for the engine also. it is variable venturi carbuereted too.

[Schmozilla]

it doesnt really matter other than it will sound like shit...

[ridin44s]

i might run a cherry bomb or something but i was just worried about burnt valves or running to lean. anybody else have any experiences?

[4x4not]

My last run out I ripped the muffler off and bent the crap out of my tailpipe so I was dumping straight out of the cat (4.0L with Banks POS header and stock exhaust). It was LOUD on the trail, and got annoying pretty quick. I cut the tailpipe off the other day and just bolted the muffler back on for the time being (straight through muffler dumping out the back - no tailpipe). It isn't much quieter than without the muffler, and sounds like crap. I need to do something before my next trail ride because it is going to drive me mad. I am toying with the idea of cutting the cat off, moving it as far forward as I can, then running a glasspack or something and then a downturned tip or out the side. It is just too hard to fit a tailpipe in there, but if I have to I have to. I just need something that takes up little space so I can finally build and install a flat skid.

[Yota Tony]

I've only got a cat on my 4.0L, it dumps right off the cat. Sound isn't bad imo but it's loud.

With out a cat or muffler you'll be fine as long as you don't have emissions in your state.

[4x4not]

I forgot to mention... my 97 only has the single cat right before the muffler. My buddy has a '00 TJ with the three cats (two precats at the header, and then the standard cat like mine) and his just has a 90° pipe dumping right out of the cat. His sounds AWESOME. Not too loud, and not drone-y. I tried the same with mine and it sounded horrible.

[y-townxj]

i heard a yj, with a strait pipe and a single stack and thought it sounded sweet but, some what like a tractor :laughing: but still sounded good

[iispms]

I have a 99 TJ with a 4.0L. I run a cat only with a small extension and it is fine. It is not loud at all, but louder then stock.

http://www.maclaughlinstudios.com/Website/images/DSC05262.jpg

The factory cat is protected by the skid plate.

[AlSwope]

I ran a 258 with just a cat and 2" all the way back. I liked the sound. It reminds me of the whine that the Jeeps on Mash (TV Show) always had.

[Ferrell's YJ]

Well I had the local 4x4 straight pipe mine from just past the cat. I dont know how emissions will react, but o well if it fails I will just have a muffler put on. I am not up to date on the state laws for driving anyways.

Ferrell

[Mohadeab]

Been running no muffler on my Ranger..no problems..sounds better too

[geberhard]

I checked with my buddy with emissions, as long as the cat is there, no problems, and for emisions in Cali the cat is required, along sensors. I had to remove my muffler for teh anti-wrap bar, and it sounds ok, a bit louder, but not that bad.

Gui

[Bboarder24 7]

i just run a cat outa my 4.0... Not bad below 2grand.

[Geesh]

I run a muffler, the quietest I can get, cause getting in the backwoods is more fun without all the damn noise, IMO.

Being behind a loud rig on a trail ride is almost as bad as being behind a smoker

[Yota Tony]

i heard a yj, with a strait pipe and a single stack and thought it sounded sweet but, some what like a tractor :laughing: but still sounded good

Yea, mine sounds tractorish at a cruise, kinda hard to get use to.

[JohnnyJ]

I liked mine best when I was running straight 2.5" pipe after the cats (01 TJ, so I've got the multi-cats) and dumping out the back. It had a good healthy sound, enough that a few people asked if it was a V8 due to the deeper growl.

I since shorted pipe and it dumps underneath the jeep, and it changed the tone. I don't like it as much, I need to get it back to the muffler shop and have them rework it around the latest suspension setup.

[currupt4130]

I checked with my buddy with emissions, as long as the cat is there, no problems, and for emisions in Cali the cat is required, along sensors. I had to remove my muffler for teh anti-wrap bar, and it sounds ok, a bit louder, but not that bad.

Gui

I squeaked a cherry bomb next to my traction bar

[ashmanjeepXJ]

I checked with my buddy with emissions, as long as the cat is there, no problems, and for emisions in Cali the cat is required, along sensors. I had to remove my muffler for teh anti-wrap bar, and it sounds ok, a bit louder, but not that bad.

Gui

You will need a full tail pipe exiting out the rear not just a down pipe if you have emissions testing. I used to keep my tail pipe and clamp it on for emissions then take it off (cat-glass pack remained). Now I run the tail pipe through the cut up wheel wells. keeps the muff and cat out of the way.

http://www.wheelingarizona.com/forums/files/exhaust_tube1_264.jpg

http://www.wheelingarizona.com/forums/files/exhaust_tube2_347.jpg

Through the body
http://www.wheelingarizona.com/forums/files/exhaust_tube3_590.jpg

And Through the frame.
http://www.wheelingarizona.com/forums/files/exhaust_tube4_136.jpg

[JeepCrawler98]

I run a muffler, the quietest I can get, cause getting in the backwoods is more fun without all the damn noise, IMO.

Being behind a loud rig on a trail ride is almost as bad as being behind a smoker

x2, I like wheeling to get into nature; not to cover it up with noise.

[4x4not]

I ran a 258 with just a cat and 2" all the way back. I liked the sound. It reminds me of the whine that the Jeeps on Mash (TV Show) always had.
Woh, Al! Long time, no see! I can confirm that Al's YJ sounds great :D

[Cheepin]

When I did my flat belly I had to pull the cat but I squeezed in a glass pack and managed to run the pipe out the back in the stock location.My glass pack does rub the shock (stock location) a little.Will probally move the shocks outside the frame sometime.It is a little louder than stock but not annoying.I don't like having a loud ass rig on the trail.Gets to be really annoying.I even shut the radio off when wheeling.

[MudTJ]

mines a 99 TJ(just 1 cat) chopped right behind the cat when i did the 4 link, i planned to get a new exaust routed but it actually doesn't sound bad so ive left it for now. As long as i'm at idle or close to it i can hear a spotter just fine, when its revved up thats a different story but whose listening to a spotter when the motor is bouncing off the rev limiter anyways:smokin:

[Travis Waldher]

Before you guys start running no muffler - keep in mind, most areas require the use of a spark arrestor.

Last I checked, cherry bombs didn't count.

[ridin44s]

Before you guys start running no muffler - keep in mind, most areas require the use of a spark arrestor.

Last I checked, cherry bombs didn't count.

i am pretty sure anyone that has looked inside a cat would consider a cat a spark arrestor.

[ridin44s]

I squeaked a cherry bomb next to my traction bar

is that an i-4 or the i-6 and how loud is it. i have almost an identical configuration and i will not be able to fit the flowmaster with a traction bar. i was going to run a single link trac bar not a ladder bar too? does it have to be on the passenger side? thanks for everyone's help.

[Doc Holiday13]

I have a 258 with a Cat and 2.5" pipes in and out of a flowmaster exhaust. It almost sounds like a muscle car. i haven't made up my mind if i like it or not. I'm sure it'll be louder when I drop my 4.0l head and headers in with 2.5" pipe from the headers to the cat

[Travis Waldher]

i am pretty sure anyone that has looked inside a cat would consider a cat a spark arrestor.

Maybe, but would your local BLM, DNR, etc. officer consider it one. ;)

[currupt4130]

Thats a 4banger, having the traction bar on the pass side is better, but not entirely necessary.