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Quiet Exhaust, slight increase in MPG and HP

jmsull

NAXJA Forum User
Location
Chicago
I'v searched, a lot, and I'm not sure there is a concensus on this but I'll ask more specificly, maybe I'll get the answer I'm looking for.

I would like to replace the exhaust on my '99. I would like something quiet, a little louder than stock is fine but I would still like to keep a low profile. I would like to see a slight increase in MPG and HP but I'm not expecting much. It is a DD and I live in Chicago, so lots of stop and go traffic.

I plan on getting a Magnaflow high flow cat, so the question is what muffler and what size pipe, 2.25 or 2.5? I figure bigger is better but I willing to be proven wrong.

I'm thinking Flowmaster Delta 50. Some say it's louder than they thought it would be, some say its fine, some say it's not loud enough. My question is, is it way louder than stock, or just slightly louder? Is there anything else I might consider?
 
jmsull said:
I'v searched, a lot, and I'm not sure there is a concensus on this but I'll ask more specificly, maybe I'll get the answer I'm looking for.

I would like to replace the exhaust on my '99. I would like something quiet, a little louder than stock is fine but I would still like to keep a low profile. I would like to see a slight increase in MPG and HP but I'm not expecting much. It is a DD and I live in Chicago, so lots of stop and go traffic.

I plan on getting a Magnaflow high flow cat, so the question is what muffler and what size pipe, 2.25 or 2.5? I figure bigger is better but I willing to be proven wrong.

I'm thinking Flowmaster Delta 50. Some say it's louder than they thought it would be, some say its fine, some say it's not loud enough. My question is, is it way louder than stock, or just slightly louder? Is there anything else I might consider?

I wouldn't waste money on the cat unless you need a new one, they are all pretty much "high flow", you can see right through them.
Bigger isn't always better here, some back pressure is needed, 2.5" should be ok, but no bigger (unless you have a stroker)
I haven't heard a Delta 50 but a 40 is pretty loud.
I think you can go to flowmasters website and hear the difference between them.
 
i havent looked in a while but at www.exhaustsoundclips.com then have sound clips of a lot of cars and a 4.0 might have a clip on there. as far as flowmaster goes 40 series are the loudest, then followed the 50 series. i wouldnt waste your money on some name brand muffler when you can get one for $40 or $50 that sounds just as good and flows just as well also
 
ok i just checked and there are clips with the 40 series, 50 series, and a borla catback that you can listen to
 
ross said:
i havent looked in a while but at www.exhaustsoundclips.com then have sound clips of a lot of cars and a 4.0 might have a clip on there. as far as flowmaster goes 40 series are the loudest, then followed the 50 series. i wouldnt waste your money on some name brand muffler when you can get one for $40 or $50 that sounds just as good and flows just as well also

Yeah, I knew there was a site with sounds, just wasn't sure where.
The advantage to flowmasters is they are really strong and hold up well to bashing on rocks!
look @ Ebay, they don't really go bad so I wouldn't hesitate to get a used one cheap. They usually go for about $30 or so on there.
 
I have the magnaflow exhaust and the flowmaster 50. I can't wait to take the flowmaster off - it's way to loud for me. It's more fun wheeling in the wilderness with a quiet ride......the loud rumble is just for show anyway....go stealthy, especially on the trail, it's easier to hear the things you need to hear.

I did go to the 2.5" pipe and the K&N conical airfilter with the fipkII intake upfront - it's all about airflow ya know. In the end, supposedly I increased horsepower (not sure I can tell), but I definitely lost mpg's (easy math there), and realized all that money was poorly spent.

Why poorly spent - I could have regeared for less $, or bought a transfer case skid, or rocksliders, or one ARB locker.......those things we really need on the trail.
 
I ran a Walker turbo muffler and 2-1/2" exhaust on my '88 (non-HO) for several years. It wasn't terribly loud, but it didn't sound especially good, either. When it rusted through and I replaced it I went back to an AutoZone stock replacement muffler and a stock 2-1/4" tailpipe. I got back more low-end torque and regained about 2 MPG.

If economy is what you're after, stay with the 2-1/4". Keep in mind that it is nearly impossible to increase power and increase gas mileage at the same time.
 
Take a tape and spend a little time in the parts department. Look at stock type mufflers off cars with big V8 and trucks to. You WILL need to do a little cutting maybe welding. IM using an Imperial muffler now but the tale pipe was bent for me. You don't have to be loud to make a little extra power. Most just like it that way.
 
tdr1213 said:
Why poorly spent - I could have regeared for less $, or bought a transfer case skid, or rocksliders, or one ARB locker.......those things we really need on the trail.
Man, how much did you spend on the intake and exhaust mods? More than what it takes to regear? :lecture:
 
So it seems like a few of you are saying I can just go and get a stock replacement muffler at Napa or where ever and I'll see the same kind of performance in city driving as I would with the Flowmaster, is this correct? the only reason I was planning on spending the money on the Flowmaster was I figured it would be an improvement in performance (however little).
 
You won't see that much improvement! My sugestion is to get a cheap one or a stainless muffler. I had the Flowmaster 50 and it rusted through in about 18 months. From the inside-out. It rusted through the can at the welds holding the baffles in place.
 
Just get a glass pack such as a cherry bomb it will be a little louder than what you prolly want but only if your getting on the gas, but it will give you great gas mpg. Also the are not as easy to drag off because they are round and don’t have any edges to catch on rocks and if do drag them on a rock or two it will do little to no damage because the will just slide on what ever surface you are making contact with....also did I mention that they are cheap, and they don’t sound that bad either....
 
Even though I suggested Flowmasters earlier I too have a glasspack right now. It really isn't too loud, but I personally don't care for the tone. They are great for not getting caught on stuff, this was the demise of my stock one.
I have seen lots of flowmasters hold up well (without rusting), and this will most likely be my next choice, but I plan on running duels just for the hell of it, so it will be a single in and dual out.
BTW my glasspack was like $15 or so. It has rusted some but has held up well for over a year.
 
tdr1213 said:
Why poorly spent - I could have regeared for less $, or bought a transfer case skid, or rocksliders, or one ARB locker.......those things we really need on the trail.

You found an ARB, and a place to do gears for less then $200!?


bad comparisons
 
I have a Catco high flow cat and a DynoMax Super turbo cat back on my 93. I like it, not as loud as most exhausts, but more rumble than stock. Here's a write up that helped me make the dession:
http://www.rockcrawler.com/techreports/dynomax_xj/index.asp

It's a direct bolt on, and a shop could probably take the old one off and install the new system with welds pretty cheap. The case is all aluminum, and it sits at about the same hieght as stock. It won't stand up to rocks, but most won't anyway.

I bought my cat back from summitracing.com for $130 shipped to my door. Your year wouild be the same:

http://store.summitracing.com/defau...earchinresults=false&N=0&target=egnsearch.asp

If you are looking for a tough as nails muffler for offroad, I'd say SpinTech has the muffler for you.
http://www.spintechmufflers.com/spintech/spintechindex.asp
 
i bought the pipe and muffler from TurboCity - Rock-it. I like that it is 2.5", already prebent and bolt/weld direct replacement. It does not sound like a bee in a tin can - not much noise increase, but seems like better throttle response.

2 1/2" diameter mandrel bent aluminized mild steel exhaust system designed and built in-house by ROCK-IT PARTS. Utilizes MAGNAFLOW muffler with a straight thru flow design. This muffler was selected to produce the most power and it has the best sound. It's quite at cruising speeds, but lets you know it is a performance exhaust when required and it does not produce the undesirable resonance inside the vehicle. Easy install and a limited lifetime warranty. Tip exits in the stock location and is turned down like stock to keep exhaust off the back of your Jeep. FITS 2000, 2001, 2002 Cherokee limited, classis, and sport models.
http://www.turbocity.com/product_info.php?cPath=17_49&products_id=93
 
jmsull said:
I would like something quiet, a little louder than stock is fine but I would still like to keep a low profile. I would like to see a slight increase in MPG and HP but I'm not expecting much. It is a DD and I live in Chicago, so lots of stop and go traffic.
QUOTE]

Sticking my neck out here and breaking from the consensus I think you are going to be unhappy with anything but a stock muffler from what you've written. Listening to soundbite samples on the internet gives you a feel for the tone of a muffler but tells you nothing about the volume particularly when you are in the vehicle. If you want to have to yell at your passengers to be heard than I stand corrected. I have a Flowmaster 50 so I know. My girlfriend tells me she can here me entering the neighborhood from 6 blocks away. XJ's are not known for their sound insulation and Flowmaster makes mufflers for motorheads like us. Good Luck with whatever you decide.
 
WOW! I really appreciate all this help, thanks. So I think I can certainly rule out a Flowmaster 40 and even the 50. I would like somthing durable, I don't do much wheeling but it would suck to ruin the thing the one time I get out a month, thats the main reason I was thinking the 50. I would also like something that can last a few winters around here. For those not familiar, in the winter they put down more salt than you can ever imagine, if there is even a chance of snow they have the trucks out all over the city, covering the streets, needless to say things rust pretty quick around here. I can get a killer deal on a Borla (stainless, solves the rusting prob) but I get the impression it is pretty throaty. I don't want to give the impression that I'm against a little rumble, but not one you can hear six blocks away. Anyway if any one has anything to add please keep it coming, I'd be curious what you all would have to say about the Borla cat back or the Dynomax Super Turbo system Balloo suggested. Thanks again.
 
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