muffler or straight pipe??

[1987MJfreak!]

I was wondering if anyone had could tell me if it would cause any problems to the engine if i cut out my muffler and welded in a straight pipe in its place. i have already removed the muffler and placed a straight pipe in. it sounds mean! but i put the muffler back in because i didnt know if there would be any problems with my engine with out it. i want to uncork that 4.0L and let her breath maybe opening up some untapped power. another question in have is i know that the 87 cherokee has the same engine as my MANche and they make an intake for the cherokee. will it work for my MANche? also has anyone ever installed a snorkel on their manche if so do you have any pics of it? and a review of its performance?

Thanks as always! James,

[Oizarod115]

horrid mileage?

i can't remember if it was the 4.0 or the 2.5 but one of them likes a little backpressure in the system. I'm sure someone else knows for sure.

[DirtyComanche]

People say the 4.0 does.

 

 

 

Doesn't matter. I ran around open header until I got sick of it.

 

 

 

Run a glasspack now. Lot nicer on the trail.

[Rokhound]

I run just off the cat for the wife’s truck but for you folk that has those inspection in there states I don’t think that it would pass. And I really like the sound as well

[1987MJfreak!]

I'm going to leave the cat in. maybe that will provide enough back pressure? either way it sure sounds alot more like a truck with that muffler taken out.

[DirtyComanche]

Well, there's a massive dent in the stock downpipe to clear the front driveshaft.

 

 

I figure that alone is good enough.

[CWLONGSHOT]

I agree, running no muffler will get obnoxiously loud. The neighbors and jonny law will not appreciate it!!

 

Get yourself a glass pack. Its a STRAIGHT THRU design and offers some reduction in sound. Once its broken in, its really got a nice throaty tone.

 

They are WAY DURABLE and CHEAP to boot!!

 

Its THE way to go.

 

CW

[mike]

i agree! put on a glasspack, i have one on my truck and it sounds good and flows free. i had a piece of pipe on there before as the muffler rotted off and thats what i replaced it with and it sounded good that way but when it's reved up it sounded like a ricer and it got annoying so i put on a 15" glasspack and it sounds good at any rpm. i have a 4.0 5-speed in my truck also.

[bdjr]

i have a glasspack on my 2.8 and it sounds good. throaty not ricey. and since i moved the tank i can run true duals all the way out the back. just have to wait for the crossover to rot through. come on rust :brows:

[CWLONGSHOT]

I posted a couple video clips of my two jeeps exhaust notes.

In that other thread about exhausts going on now.

 

http://comancheclub.com/forums/viewtopic.php?t=2497

 

CW

[redneck_rollercoaster]

I have a 4.0 with a straight pipe and a stock cat. it sounds good. also it didn't really affect my milage at least not that I noticed? I have stock pipe from the header back and run 2.5" from the cat back.

:cheers:

[mparsons]

My '90 came with the cat removed and with a stock muffler. I changed it out to a turbo muffler and really like the throaty but not loud sound. I hate glasspaks on a straight 6. Sounds like a bean eater!

[beaterjeep]

I got an 86 with the 2.8L that has no cats and dual glasspacks, and I kinda like the sound it gives off. My only problem is that the local cops don't care for it, I just tell them that's the way I bought it and they leave me alone.

[GirsMJ86]

I got an 86 with the 2.8L that has no cats and dual glasspacks, and I kinda like the sound it gives off. My only problem is that the local cops don't care for it, I just tell them that's the way I bought it and they leave me alone.

 

yea and it sounds like you are being fired at when it back fires, unless that got fixed for ya. lol.

 

my 91 has a cat and a flowmaster 40 series. sounds good on the 4.0 i think. i am getting a sound clip of it for the other thread, once it is up i will let ya know. once my exhaust goes to crap (since i am in Ohio it won't be long) i am removing the cat and just doing a flowmaster again or something with a nice low sound.

 

Alex

[beaterjeep]

I got an 86 with the 2.8L that has no cats and dual glasspacks, and I kinda like the sound it gives off. My only problem is that the local cops don't care for it, I just tell them that's the way I bought it and they leave me alone.

 

yea and it sounds like you are being fired at when it back fires, unless that got fixed for ya. lol.

 

Alex

 

Nope, still backfires like a son of a if ya let off the gas quick, so I've learned to be a 2 foot driver, slowly let off the gas with the right and slowly press the brake with the left, plus this way I'm not reaching for the clutch.

At least not as much as I used to be anyways.

[GirsMJ86]

I got an 86 with the 2.8L that has no cats and dual glasspacks, and I kinda like the sound it gives off. My only problem is that the local cops don't care for it, I just tell them that's the way I bought it and they leave me alone.

 

yea and it sounds like you are being fired at when it back fires, unless that got fixed for ya. lol.

 

Alex

 

Nope, still backfires like a son of a if ya let off the gas quick, so I've learned to be a 2 foot driver, slowly let off the gas with the right and slowly press the brake with the left, plus this way I'm not reaching for the clutch.

At least not as much as I used to be anyways.

 

yea thats how i managed to get around the back firing problem.

 

Alex