Topic: Quiet muffler?

[kidwithayj]

Well, since I was redoing my exhaust anyways, I thought I'd get a new muffler. I picked up a Dynomax Super Turbo because, well, I dunno, it was cheap and I thought it couldn't be too bad. I just drove home from the exhaust shop not five miles and my ears feel like they want to bleed, not to mention it's plain riceresque obnoxious.

What's a quiet muffler? Stock is out since the shop canned it. It doesn't help that I have a turn down underneath the Jeep that makes it resonate like a sonofagun... Not to mention the heat from the cat is apparently trying to melt my clutch line...

Great way to start the weekend.

[Jeffy]

Go with a stock muffler.  Everything else will resonate at some point and drone at aothers.

As for the cat. How is it even getting close to the clutch lines?

[kidwithayj]

It's close to the clutch line because I swapped in a non-flipped Dana 300 and had to run my exhaust down the driver side. The exhaust shop welded the cat right on to the first section of straight pipe off the down pipe, they didn't put it above the skidplate like stock is located.

There is a clutch line retaining strap that hangs on one of the lower bellhousing bolts, I moved it up to the next bolt and it pulled the clutch line about 6" farther from the cat. I could also get some more of the woven heat resistant webbing that already covers part of the line. Nonetheless there's still some pretty significant damage to the line, it needs replaced. I'll have to keep an eye on it.

You run a Borla, don't you Jeffy? How do you like it?

[KS98TJ]

I did something similar this year.  It seemed that my stock mild steel muffler was getting louder and I thought I could see the end of the case rotting out- carbon black and all.  So, I bought a Gibson system made of stainless steel.  I even spoke with one of their tech guys first to confirm things.  They claim "quiet power".  Well, it was insanely loud!  My ears literally buzzed.  :evil:  I figured, well, maybe I can salvage this and put a regular muffler on and still get the life out of a stainless pipe.  My local shop put a Goerlich Turbo muffler on it; a standard muffler would have been too long to fit.  Well, it was still too loud.  Anyone want a loud exhaust with only 8 miles on it?  I'm selling it in the ads section.  :wink:

I went back with a stock muffler.  Well, in the end, the whole thing is louder than when I started!  :x   I've even had a backfire or two in the beginning and now I can swear I hear an occasional rattle underneath.  I did cut apart the original muffler.  It turns out there was nothing wrong with it.  Arrgggh.  I was just getting extra carbon out the drain hole.

I did modify the new factory exhaust (stainless and three times the cost of the old Jeep stock system) by shoving one of the original muffler baffles up the tailpipe.  I get an annoying midrange resonance that the Dynapad I put in the rear bed doesn't quite soak up.  It's not loud, but annoys me a bit because I know it's there.

I even asked one of the parts guys at the NJ dealer I get my Mopar stuff from if they'd noticed the new exhausts being louder.  He said yeah and that the techs were told by D-C at a factory training session that it was done for performance and emissions.  Looking at the 2000 parts catalog, I notice that the only part # used these days is actually the 4.0L exhaust.  There were 2 different Mopar part #s, although the external dimensions on all Jeep exhausts are identical.  In my "autopsy" of the original muffler, I found that, although the inlet, outlet, and tailpipe are all 2.25" in diameter, the through-pipes and baffle pipes in the muffler are only 1.75" in diameter.  To be honest, there's no way the 2.5 L needs the same flow capacity as the 4.0L, so this is plenty.

I blew way too much cash this Spring, but I may trash the new muffler at some point anyway.  I may have an aftermarket regular steel muffler welded to the tailpipe (rear only) and slip fit up front in the end after all.  I guess one has to make a fool of himself every few years and waste some dough...  :oops:

I'm even going back to paper filters in my trucks.  After cleaning and reoiling the K&N in the Suburban a couple of years back, there's no way I'm doing that on a computer-controlled vehicle.  It's one thing on a carbed 350 with no computer, but a different animal on an MPFI powerplant.

Good luck.  I know how you feel!  :?

[Jeffy]

Yes, I run a Borla and don't find it that loud.  It's pretty quiet unless I get the RPM's over 3700 then it will start to resonate.

If I was going to futz with a muffler, I'd probably get a supertrap.  This will allow you to adjust the sound level/backpressure with more plates.  They come in different sizes and would get the the muffler out of the way.  Although there might be some legal issues depending on where you live.  You'd have to remove the baffles to get emissions done too.

With that said, after spending money on a Flowmaster and having it break off , I vowed to buy an exhaust once.  I've had to get my Borla replaced a few times.  I'm on my second muffler.  One of the problems with the 2.5L is that it has more vibrations then the 4.0L which can cause thigns to break more frequently.  I broke all the hangers off my current exahust and could probably get it replaced but the muffler works fine and I have it supported by turning a clamp into a hanger.  So far it works great.  A replacement would only cost me the price of shipping the stuff back to Borla. (around $8-14.)

[upnorthbacon]

I'm going throught the same muffler process.  I put on a dynomax and it's way too loud.  I never thought of looking into supertrapp though?  Maybe I'll check into that.

[kidwithayj]

I got a tailpipe bent and put on, it quieted it down a lot. It's decent now and I really only notice it at idle and full throttle. I think I still prefer the way the stock muffler sounded (ie, it didn't), but this will work.

[Krod]

If you dont have a tailpipe, its going to sound like a semi.   PERIOD.   I've been down that route (thanks to the awesome rocks at Rausch Creek   ).

Buy a dynamax tailpipe and have it modified to fit closer to the crossmember/frame.