Exhaust Q's

Collin the Hen

New member
Hey, guys
I have an 84 CJ7 with the 258. Pretty soon I'm going to be fixing the floorboards and body mounts so while I'm at it, I might as well figure out my exhaust.
Right now, it has a catalytic converter that goes into a muffler, and my tail pipe rusted off. Would removing the catalytic converter give any more power? Emissions here in Indiana are pretty much, if it runs... it's legal. Or, should I just buy a new muffler? I don't want to buy a header and full exhaust yet because, well, I don't have the kind of money to throw out.
The thing that bothers me is that I have an inline 6, and I can barely hear it! I want to hear that torquey growl! :piratenanner:
 

You might get some more power out of it, but probably not enough to feel. Are you looking to run no muffler, or just a louder one?
 
Well, my idea was to take out the cat and run some type of higher performance muffler, but if removing the cat doesn't do much, then I'd just keep it on. I've heard that the "new" cats are built in such a way that it doesn't hinder performance much, but I've also read about some guys who take it out of their ricers and claim up to 10 hp gain. I'd say it's a placebo affect, but I'd just like to hear from fellow Jeepers.

Someday, though, I'd like a set of Headman Headers with dual outlets then have those go straight into a couple glass packs. My friend has it on his CJ7 and it sounds mean!
 
I don't think you'll ever tear up the street with a 258 and big tires. I'm not sure that I'd put alot of money into headers. I'd be more tempted to buy some sort of cherry bomb muffler, or even disconnect the existing one.

Take a look at this:
http://www.jeepz.com/forum/exhaust/16928-installing-new-cat-back-exhaust.html
you can really hear the difference when in the first mp3 - the one with a hole in the muffler. Try disconnecting your muffler and see if you like the sound.
 

:lol: I know that! I can at least make the 258 have some ego. Thanks for the advise, Terry, you always have something good to say.
Any other advise is appreciated, you timid viewers. :mrgreen:
 
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removing the cat from the system WILL increase the power.

how much is questionable. highly doubt it would be enough to feel...likely less than 10hp.

it WILL make the car sound different, you may end up with more rasp when you get into the upper rpms.

i say pull the cat, and put a magnaflow 4x9" straight through muffler on it.

i have those mufflers on my cat-less exhaust for my camaro....very nice sound.
 
I may try that. The thing I'm worried about is how my exhaust will smell. I guess I'll really be able to tell if I'm running too rich. :purple: I'll post my setup when I get around to it. Again, this will be after I get my frame and axle stuff done. Thanks for the info!
 

straight pipe it!!!!!!!!!!!!

PUT STACKS! :purple:

Most of the 258 sound good with a dual outlet header and mufflers. The muffler will depend on your opinion on the sound. Most aftermarket mufflers dont have a big difference in horsepower or torque. Dual 2 1/4" exhaust will work great for the balance between power and torque, even a single 2 1/2" would work. If you go too big you will lose torque and horsepower. The 258 is not a race engine unless you make it one.
 
Dual outlet headers would be nice and sound pretty cool, but I've got some other more important things to invest in... like a weather proof cabin! Yesterday, I saw a piece of my right panel lying on the ground :roll: It doesn't end, guys! 1 step forward, 2 steps back with this Jeep!
 
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