• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

exhaust setup

almondjoy137

NAXJA Forum User
Location
Blacksburg, VA
hey guys,
I just bought the K&N FIPK for my 2000 and now im looking into the exhaust system. I'm pretty sure im going with a flowmaster muffler and Ive been looking around for a system that might suit me better. I was on rusty's and i saw the flowmaster system, but I saw the different muffler choices, but that's where i had my question. The choice is between the 40 or 50 series muffler, but rusty's discourages the 40 series on the I6 and say its better suited on a v8, so I was wondering if you guys had any imput on that statement or if you disagree with them. Any setup suggestions are warmly welcomed :) thanks.
 
Rusty is fairly knowledgable on most jeep matters but maybe he was just pointing out the differences on potential exhaust notes or gains. I have a 40 series delta on my '91 4.0 and also on my Titan with the V-8. Of course the sounds and gains are totally different but here goes. On the XJ you will get a nice throaty grunt where as the 50series I believe will be more mellow. I have more vibrations and a different frequency now with my 40 and high flow cat but it's still very reasonable. When it gets into the 3000rpm plus range she opens up a little and the deepness gives way to more of a raspiness. On the Titan it's quiet but when I get on it it let's you know, and anyone next to you. haha. I might have picked up 9hp on the Titan and maybe 3-4 on the XJ. So basic difference is the chamber baffles on the 40 and 50 series. What he might have meant was that because the 40 is open more internally it maybe better suited to a v-8 because of the need to move more air thru an exhaust, but by no means can you not throw one on the l6. If it's a daily driver and you just want pep and quietness somewhat go with the 50 but if you plan on adding mods and like a deeper sound try the 40, should be close in price. As far as a setup I hear good things about guys with headers and the whole 9 but couldn't help there, sorry. No need to go bigger on pipe diameter than 2.5in either. Waste of money and the l6 does well with 2.25 anyway. Hope this helps, good luck.
 
Last edited:
I have a 97 with the K&N you talk about, and the Flowmaster 50 cat back, I really like the setup. The sound is good, not sure what the sound is like off the 40 that is mentioned, I too get the raspy snarl around 2750+rpm and it did open up the exhuast a bit for maybe a few more ponies. After a week I also installed the Banks header from Rusty's and replaced the down pipe which seemed to be the limiting factor in the exhuast. Once that pipe was on the header made a few more ponies and the muffler snarled a tiny bit louder still... I certainly like the sound and the performance of the setup. I am installing a 99+ intake manifold on mine in a week or two, apparently the sound changes a little more with that on allowing more air in than my stock one does... looking forward to it.
One point tho, I got the K&N pack, and to be honest I wish I had saved my money and just got the big 9" filter and airtube from Rusty and used my stock air hose connection. I didn't feel a big gain with the FIPK, and it won't fit under the hood with a TBS where as the airtube and stock airhose would which I have heard works as well if not better and is much less money. Granted if you have it installed already or can't return it there isn't much you can do. Either way you'll feel gains with just the new intake, and the exhuast will make it sound nice too.
 
Back
Top