Exhaust Up Grade Recommendations

Hello Everyone,

I have a 94 Jeep Cherokee Sport automatic with a 4.0L engine. The jeep is bone stock except for a borla header. I am looking for a new exhaust and a high flow cat. I was think a Dynomax exhaust. I don't know what diameter my exhaust is though. Does anybody know what the diameter is? It would help my decision on a new exhaust. Also was wondering if anybody knows a good high flow Cat for the Cherokee. Thanks for the help.

GingerXJ94

I like the DynoMax muffler and pipe-real nice kit. But, at not quite two years, I'm seeing the start of a hole in the muffler, and the tailpipe looks to be very rusted. Although, I'll bet Georgia doesn't spray their roads with the caustic crap like they do in PA....

Exhaust system stock is 2.25", from cat flange to end of tailpipe. Go any bigger, and you may lose any scavenging effect from the system.

Dynomax is sweet when you consider, full price is about $150 and often dynomax has a $50-75 dollar rebate!!! The sound is perfect IMO loud enough that it isn't stock, but not annoying at all, and zero drone. Its perfect and maybe even a bit too quiet! It has gotten quieter over time, i've had it on for about 8 months now. Even if it rots out every few years, for $100 bucks (i bagged it on a $50 rebate) its worth it IMO.

As for high flow cats, ehh not really worth it. A regular cat will usually cost less and flow well enough that there is no use in anything that can technically flow better. I bought the direct fit magnaflow cat (hint: find that part number and search it on ebay, i got one for $100 shipped, new)

There are 2 Dynomax kits- one is 2.25, other is 2.5. If you search a bit, it's been discussed on here many times. Part numbers, where to buy, rebates, the whole nine yards.

You can get a spun high flow 2.5" cat with or without bung for under 40$. And I prefer Aero Turbine, magnaflow/bullet performance mufflers, or the dynomax ultra flo's AS far as cat-back kits the dynomax is the cheapest one, esp with rebate. I, myself, do not like exhaust tips much so I use a muffler and a turndown.

Hi-Flow cats are about worthless except they do help a little. They make your wallet lighter, so the Jeep weighs less
BTW, it's illegal to replace a working cat anyway.
Now, I know, they'll be some floppy headed muppits around that will advise you to punch a hole or some such similar cr#p, in your existing cat.




Fred