Topic: Performance Exhaust for 2003 TJ with 2.4L?

[kkoomoa]

Does anyone know or can recommend a performance exhaust system (pref a cat-back system) for a 2003 TJ with a 2.4L? Every parts house and manufacturer I've contacted tells me that they do not have one or make one that will fit. The only recommendation I have received is to have a custom exhaust system fabbed, which will probably cost a lot more than I can afford.

[Jeffy]

Borla?

[Bounty Hunter]

What are you wanting to achieve?  The stock exhausts flow pretty well.  I'd either have a shop install the muffler of your choice, or have them bend you new pipe if that suits you.  Not as expensive as you think, my local shop would be less than buying a system from a retailer.

[kkoomoa]

I contacted Borla directly and they do not manufacture one either. I suspect that since most exhaust systems made for my year of TJ falls into the 97 thru 06 TJ's with the 4.0L or the 2.5L. Since the 2.4L seems to have been manufactured in smaller numbers, I'm guessing it just isn't cost effective for anyone to manufacture one for this model. Plus I've checked with Jeep and the pipes for the 4.0L and 2.5L will not work on the 2.4L at all.

Everything I've read so far indicates that a performance exhaust system will increase my overall performance, nothing huge but a bit. Since I have added a Jet chip and an air intake, which did have a performance increase, I'm hoping to round things out with a better exhaust system. A performance exhaust system is supposed to reduce back pressure and in conjunction with the air intake , should squeeze a few more horses out of the engine (or at least that is what I am hoping to do). I really haven't found anything about the stock exhaust on a 2.4L and whether it has good or bad flow. I've also read that mandrel bent pipes perform better as well, which mine are not. Having the 2.4L, every little bit helps.

I have been holding off in going into a shop hoping to find a cat-back system I can install myself, believing it would probably be cheaper as a do-it-yourself job. But I'll take your advise and go on in, maybe it will be less painful than I thought. It's certainly worth a try. Thanks!

[Jeffy]

I contacted Borla directly and they do not manufacture one either. I suspect that since most exhaust systems made for my year of TJ falls into the 97 thru 06 TJ's with the 4.0L or the 2.5L. Since the 2.4L seems to have been manufactured in smaller numbers, I'm guessing it just isn't cost effective for anyone to manufacture one for this model. Plus I've checked with Jeep and the pipes for the 4.0L and 2.5L will not work on the 2.4L at all.

Everything I've read so far indicates that a performance exhaust system will increase my overall performance, nothing huge but a bit. Since I have added a Jet chip and an air intake, which did have a performance increase, I'm hoping to round things out with a better exhaust system. A performance exhaust system is supposed to reduce back pressure and in conjunction with the air intake , should squeeze a few more horses out of the engine (or at least that is what I am hoping to do). I really haven't found anything about the stock exhaust on a 2.4L and whether it has good or bad flow. I've also read that mandrel bent pipes perform better as well, which mine are not. Having the 2.4L, every little bit helps.

I have been holding off in going into a shop hoping to find a cat-back system I can install myself, believing it would probably be cheaper as a do-it-yourself job. But I'll take your advise and go on in, maybe it will be less painful than I thought. It's certainly worth a try. Thanks!

You might want to compare the exhausts of a 2.4L with a late model 2.5L.  I suspect the exhaust isn't much different after the cat.  The 2.4L was just a stop gap till they got the JK done.

[streetmaster]

Well im not sure about performance parts for the 2.4L, but in any event, while pulling onto the hyway today. A friends TJ went buzzin past. It was an older 2.5L TJ, older than my 04 with the 2.4L. He has just a stock wheel and tire combo, and was doing probly 65mph nothing special  . I wanted to see how long it would take to catch up and maybee blow his doors off. So i blew past him at 80mph  He looked over and grined because he knew what i was up to  My Wrangler GSA P225's are an inch taller than his stockers. IMHO if you drive her right, i wouldnt spend $ on performance exhaust, go with gears.

[aw12345]

yup the little 2.4l 4 popper does just fine. Climbs the mountains just as well as my nissan frontier 4 door 4x4. It actually will corner faster also go figure

[kkoomoa]

Thanks! I will take your advise and look at re-gearing instead of an exhaust system. What ratio would be best? I'm currently running 31's.

[Jeffy]

Thanks! I will take your advise and look at re-gearing instead of an exhaust system. What ratio would be best? I'm currently running 31's.

Need to know what transmission it has...

[streetmaster]

Go to the (Facts and nothing but the FAQ) page #2 go down to Regearing for your 4banger, and that should give you an idea. With 31,s you should go with 4.56's to run like stock. If you stay with 4.11's you might drop 2 to 3 hundred rpm's with the 31's. The way i look at it is, if im gonna go threw the trouble to regear, it'll be with a set of 4.88's and a set of 32's and a BB and that lil 2.4L will still hum like stock.