Thinking about doing exhaust....

[5.4 speedster]

I know that the subject has been beaten to death but Im going to ask anyway. I want to get a bit more power out of my 4.0 grand cherokee and I am thinking about doing an exhaust system. Down the road I plan on getting a borla header, I know headers are prone to cracking but borla has a killer warranty and I would be doing the work myself so Im not worried about labor.
As for right now I would like to do a catback exhaust. Has anyone used a mac muffler or heard one? I have mac on my mustang and I love the sound. Granted, its a v8 but Im curious what a mac muffler would sound like on a 4.0?
Also, any thoughts on whether or not I should get a mandrel bent system or just buy the muffler I want and have someone fab me up a system?

Thanks for the info

[spd33]

Don't count on the exhaust really making any noticeable power gains for you. As for whether to buy a pre-fabbed mandrel bent system or having something bent up at a muffler shop, it is really a matter of budget. Tossing a muffler on with some slightly larger crush bent piping is likely the far cheaper route.

I've used Mad Hatter on Broadway and Gilbert for numerous exhausts on various vehicles including 3 4.0L Jeeps.

(edit: I was mistaken, it is Mad Hatter I've used, not Mighty Muffler although I've had work done by them as well)

[AZJeeps TJ&XJ]

You don't have to run a Borla header, you can run something a bit cheaper. As for piping, if you can run a 2.5" from front to back, then that will be more then enough as it doesn't need to be mandrel bent. The 4.0 is not a serious HP monster so some of the things that are done to big motors, doesn't have the same effect on the 4.0.

I haven't heard of a Mac muffler before, so I can't give any info. But I like running flowmaster's, they perform well, sound good, and hold up to some minor rock rash. Then again I have one XJ that is straight piped after the cat and it can sound mean. But for the best performance, you want a muffler that has little restriction. So I would say get a header, and a decent muffler, then have a 2.5" pipe fabbed up, and save a lot of $$$ rather then buying a kit.

[5.4 speedster]

well I heard they all crack so thats why i wasnt worried about paying extra for the borla (lifetime warranty)

[drroadie]

X2 on the flowmaster. I run there cat back system, and love the sound. Doesnt dron on the highway, but sounds great on the low end. I think I got a bit of improvment in performance as well. Cought it on sale, so I don't think Mighty Muffler could have beaten the price. Did have them (the one on Cave Creek Rd.) fab a system for a pick up once, and was very pleased with that too. It's hard to make a mistake, as long as the motor breaths better when you are done.

[Tom Schenk]

I ran a Dynomax cat-back on my 4.0 and was happy. It sounded good without being loud. Power gains :rolleyes: maybe combined with an intake but I wouldn't hold my breath.

[5.4 speedster]

i went with the dynomax kit. ill let you know what i think

[FrenchChili]

Banks Torque Tube Headers, had those on my baby, woke it up and was crying:D