TheDodge

Hi Jeep-sters!

I have a virtually stock '99 Cherokee Sport 4x4. Bought the thing new 10+ years ago and have loved it - even at times babied it - ever since. I originally didn't want to modify it in any way, but now I'd like to start. I wanna change out the exhaust system and I'm looking for suggestions on what works/performs best - for the right price of course. Nothing over the top - just a no-frills-all-around performance exhaust system. Particularly, what are the choice header and cat back system combos that you know work really well?

Any guidance would be much appreciated - thanks!

Dsandine

It all depends what you want out of your jeep. As far as headers are concerned, it looks like all that are available for the 99 have a 2" collector (which is a bit small IMO), pace setter makes one that has a 2.5" collector (you might loose a bit of low end and gain top end. I have read from a few different places that 2.25" collector is best for mildly modded jeeps so do you want a bottle neck 2" with good low end or a bit bigger 2.5" with more power higher in rpm range. As far as catback exhausts IMO they are all junk, from a performance standpoint, if you wanted to do cat-back the best way (and its cheaper than alot of other catback kits is get the 4wd stainless catback kit and don't use there junk turbo muffler, simply use a spintech instead (http://www.spintechmufflers.com/) That setup will outperform any of the other kits and is cheaper than most even with the cost of an additional muffler, and maybe you can sell the junk turbo muffler and get a little back. Then just find a high-flow cat the same diameter as rest of exhaust (aftermarket high flow cats actually flow worse than the cats that come on new cars so you should have plenty of back pressure) and you will be set. But that is just what I would do.

Combat_Gunner

The OEM header doesn't flow bad, but almost all of them crack at some point, because they're very thin. Quadratec sells a Rugged Ridge header that's pretty affordable, and you can find them on ebay also. Almost any muffler will be better than the stocker. I've been going around listening to a bunch of Jeeps with different exhausts for months, and I gotta say that I definitely prefer the Flowmaster Super 44 in either 2.5" or 3". Some folks don't like the interior resonance they get from Flowmasters, but I think it's the only muffler that doesn't sound ricey. Stock or hi-flow cat won't make much difference in power on this engine, unless you've got a stroker or V8 conversion. The Dynomax cat-back is a good value, and you can get it from Summit Racing or Quadratec, among others. Dsandine's suggestion would work, and you can choose your muffler for the sound you prefer. As for me, I'll be ordering this muffler and taking my XJ to the local speed shop to have them mandrel bend a fresh tailpipe routed out the side in front of my RR tire.

Whatever you do, don't buy a muffler based on somebody else's opinion. Muffler sounds vary widely, and until you've heard one in person, you won't know if you like it. Nothing sux worse than spending money on a muffler you hate two weeks after it's installed.

Dsandine

You should check this out, different mufflers and a decent amount of sound clips in that thread.

Also one thing you have to keep in mind is "the dodge" wants the exhaust that works/performs the best, and with a multi-chambered flowmaster (even though it seems to be by far most popular in terms of sound) the performance gain will be negligible, or nothing at all.

Also one thing to keep in mind is if you get any baffled muffler the baffling will wear changing the resonance and thus not flowing as well once whatever baffling material wears, but I have no idea how long it takes for the baffling to wear.

djb383

Personally, I like the "lack of noise" (so do the neighbors), straight-thru, stainless steel, unrestricted flow/design of a Magnaflow. If you open your XJ up with a smooth open flow header, why cork it with a baffle/chamber muff. LOL

cob24

If you look in the vendor specials section there is a guy there with decent prices on some exhaust stuff

cpttuna

On my cherokees, I have the muffler shop guy cut the exhaust when the exhaust pipe starts to bend under the vehicle. He then uses the 2" ss pipe I buy scrap at the recycling center. For the muffler, a Borla universal ss with 2 1/4 in and out and a jegs universal ss cat 2 1/4 in and out. When he has it completely fabricated, he welds it together. I have pics on another site.

Dsandine

that is a baffled muffler, since it straight through it looks like its completely unrestricted, but it is not a straight pipe, if you notice their is a shell that goes around it t hat is filled with material, and over time the properties of that material change, and as I said early it changes the resonance and it is not best flowing muffler.

Tural

are you gonna do the work yourself or take it to the shop?
do you have a welder? 110 flux works just fine
are you looking for a specific sound?

like someone else already said, the stock headers flow sufficient for the stock motor, the only problem is cracking. if you have a '99, i think more than likely you will not have to worry about that. when i replaced mine it looked almost new at 155k miles. i don't know about previous years but my '99 exhaust manifold is not cast. i have flowmaster 40 2.5 and it sounds just a bit louder than stock. and that's also with a "high flow" cat.
if you do not have a stroker or a turbo, i'd say you're not gonna gain anything considerable out of an exhaust system.

djb383

It is filled with a ceramic material that wont burn out under high temp.

Dsandine

Sorry to get off topic. but that's according to manufacturer. Any material that is heated and cooled repeatedly is going to change its characteristics, that is just common. I am not talking about material burning out, just properties of it changing, which will happen. Think of it like a fancy ceramic cook top stove, after repeated heating and cooling cycles it does change.

Good thing about magnaflow is I am pretty sure they have a lifetime warranty, so if you notice your exhaust note is starting to change (probably pretty hard to tell) then you could get another one for free.

Another advantage of the spintech is you can get a race muffler that when installed on a open header car you will lose no hp or tq and it will be somewhere around 93-98 db, and that is without a cat, with a cat it would even be quieter.

I was a huge fan of straight through mufflers but have usually had to also run resonators so it wasn't terribly loud and buzzy, but I have gotten rid of borla mufflers on all my cars and switched to spintech and love it.

But once again that's just what I understand. I don't have a degree in thermal and fluid dynamics, and in the end even if magnaflow material changes you are talking about a loss of maybe .5 to 1 hp on a close to stock jeep 4 liter. Pretty soon I will post a sound clip of the spintech on the 4 liter, but for now I would go through the thread I posted earlier and get what you think sounds best, I just would not go with flowmaster, but if you really like the sound, go for it.

If you decide to buy a complete cat-back and not kind of manipulate one like I did, I would pick one out them go to summit's website or talk with manufacturer. (even though manufacturers techs have given me false information) By doing that you can find out the diameter of all the exhaust plumbing, for instance I almost bought the borla, then found out at the tail end it squeezes back to 2" diameter, which I found unacceptable, so I figured I would make my own by piecing together items. In the end I got a 2.25" collector diameter than I am having 3" spintech made that dumps out in front of rr tire.

In the end you can get whatever you want, you don't have to buy a kit, you can just buy whatever muffler you like and take it to an exhaust shop as they can fab up almost anything. (I mean it is only exhaust) I do recommend as much stainless as possible though cause rusty exhaust sucks and if you have to pull it off to work underneath jeep rusty parts really suck and often end up having to be replaced.

cob24

The link you are talking about is the spintech site? I thought you had posted another one that lets you listen to other brands too. If you have that link could you post it for us?

98 JeepJeep

fiberglass packed mufflers get sooted up and the material will harden over time...They will get louder and louder over time....

In fact they use about the same material a Stock Quiet Flow muffler uses..

Dsandine

Sorry, must have forget to throw link in there, here you go.

https://www.cherokeeforum.com/f2/bes...ght-6-a-35215/

djb383

Yep, lifetime warranty and I've run a couple over 100K miles on P/U's towing heavy loads (lots of heat). They seem to get a little quieter over time. Hard to beat a straight-thru, wide open design (similar to a straight pipe) but quiet.