Opinions on possible new exhaust

I'm going to swap out a whole new exhaust in the spring and want to see what people recommend from personal experience. My exhaust is completely stock (110,406 miles) except for a 4 year old Dynomax cat back on it now which I've really liked and year old O2 sensors. Here's what I've come up with so far.

Header: Dynomax Blackjack (comes with downpipe) or APN header w/custom downpipe

Cat:Magnaflow 2.5" or 2.25" universal high flow cat (depends on which cat back i buy)

Cat back:Rusty's Offroad 2.5" exhaust w/Super 40/50 (i know the 40 is loud, but how much louder than the 50?) or Dynomax Super Turbo 2.25"

99 XJ 4.0L w/62mm throttle body and spacer, cold air intake, upgraded complete ignition to Accel, and EDGE Trailjammer programmer... I know many people laugh at it calling it useless, but i got it absolutely dirt cheap and even though it doesn't feel as powerful as claimed I swear it made a difference

The 40 was too loud for my taste. I went with the 50. You can go to youtube and search for videos of jeep exhausts. The sound is not that great, but you can get an idea of dBs.

I like my 40, never has bothered me, can carry on a conversation and listen to the radio, my tires are louder in the cab than the muffler, however my friend has a 40 on his dumped, and that's really loud.

I have a dynomax and love it for the price.I've been hearing that dynomax gives more power than flowmaster.....

There is a link out there that shows a dynomax being dyno'd.I'll try to find it.
Here it is
http://www.rockcrawler.com/techreports/dynomax_xj/page2.asp

my setup in sig, I really like the Super 40, not that loud from the cab, but mean sounding outside.

I went with pacesetter header, dir fit converter 2.5, dynomax superturbo 2.5, and torctite stainless clamps

Any further progress on this?

I have a cat and a muffler I need to replace, and as such, I am planning on swapping the whole lot from headers back to the exhaust tip.

As such, I would think that a 2.5" setof pipes for the converter and cat back system would be the way to go for better exhaust and what not? If this is the case...would I need to choose a specific header and drop pipe that would also have a maximum flow rate? I am really looking to improve my MPG while I do this.


Thanks for any info.

I won't buy a flowmaster again, they fall apart rather quickly and are expensive to replace. For the same price as a flowmaster I bought a Magnaflow muffler that is stainless steel and has a lifetime warrenty. I should be installing it tonight or tomarrow so I don't know how it sounds yet but I only hear good things about them. There are no baffles like a flowmaster, it flows straight down the center like a glasspack, but is quieter than a flowmaster.

jeepboy381 said:

For the same price as a flowmaster I bought a Magnaflow muffler that is stainless steel and has a lifetime warrenty.

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interesting. I had a Magnablow for my other car...came out of the box with pinhole leaks in the welds and the hangers welded wrong (melted my bumper) and they told me to 'have a local shop fix it'....this, a brand new $1k exhaust supposedly welded by robots.
:doh:

I like my flowmaster 40 that I have had on 2 vehicles now and its about 3 years old and still cherry. The rest of my exhaust well... It looks good on my garage floor ha ha

PGT FTW said:

interesting. I had a Magnablow for my other car...came out of the box with pinhole leaks in the welds and the hangers welded wrong (melted my bumper) and they told me to 'have a local shop fix it'....this, a brand new $1k exhaust supposedly welded by robots.
:doh:

Click to expand...

Mine is perfect nice and shiny stainless steel with no defects. My flowmaster only lasted 3 years and it started rusting apart from the inside, this was a daily driver to so it didn't sit and rust. It was by far the shortest lifespan I have had on a muffler, my 97 XJ still had the factory crap muffler on it not leaking when I sold it in January.

The muffler shop I bought the magnaflows from said he has never had to replace a stainless magnaflow muffler. They were not always stainless though, they once were just aluminzed junk like the flowmasters.

If you wheel it, and you are replacing it all, consider having it all tucked up. I had mine tucked in between the oil pan and trans where it crosses over to the passenger side. From there back I just have a glass pack going straight out the back through a 3" double wall tip for crush resistance. Sounds pretty loud but good, and cheap.