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! :?
