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Discussion Starter #1
I've got 88'000 miles on my xk, and still have the stock cats. Has anyone replaced theirs with a high flow or after market? If so what kind? I have a gibson cat back system on now?
 

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I can't remember if you have the 4.7 or the Hemi. If you have the HEMI, this is what I did:

I bought an entire exhaust from a 8K mile Cherokee SRT8 (6.1 HEMI). THese are true stainless headers with thick flanges, bigger collectors, bigger cats and both pipes come into 1 muffler.

I threw the cat-back away.

I will cut the 3 foot muffler out because it weighs a million pounds and doesn't flow worth a crap, and replace it with a 2 into 1 system (2.5" x 2 into 1 x 3" outlet) and run the 3" in front of the passenger rear tire.

I bet you can buy everything I bought right off an SRT8 forum for $300 - $500 because its been sitting in someones garage for 3 years now and their wife is steaming hot mad about it.

THe headers will be a b1tch to put on and therefore removing the head is sound advice.................BUT.................if you remove the head, consider milling the head .030 to up your compression to 10.5:1 (static)

BUT...............since you are going to all that trouble, I highly suggest you change out the cam (maybe a 212/212, 518/518 on 114 lsa) and an SRT8 crank pully (under drive).

Now you need a Diablo tuner and have someone (i know a few) tune it out for you. That combo will make right about 385 / 385 at the wheels and at that point you really need a locker because you'll spin them regularly without fail and consider the suspension, you'll wheel hop till you break something.

And yes, that will out run most stock Mustangs, Cameros and most all ricers................and yes, in a jacked up, big tired, 2wd Jeep :banana_hitit:
 

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That is awesome advice. All I wanted was a high flow cat and all of a sudden I will have 450HPs! How much do you think that would cost because beating the "youve got a mustang/ camaro? me too" crowd would be priceless. But I am also QDII all wheel drive
 

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For Christmas I'm giving my three year old son a Craftsman socket set, and book called "If You Give a Mouse a Jeep."
 

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depends on what you can do yourself and how much you pay someone to do your work.....

$300 - $500 gets you the headers and mid section (cats)
figure $200 for a 2 into 1 muffler and some welding from a local shop
set of 6.1 SRT8 springs, install and .030 mill = $350
2 new head gaskets + new head bolts, new header bolts = $200
cam = $450
srt8 crank pulley and new crank bolt (always change these crank bolts) = $150
Diablo Pred Tuner = ??????
Tune = ?????

I figure about $1700 + tuner and tune

Wait for me to do it first and do a write up and then you can figure out if you want to do it.
 

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Discussion Starter #7
:sick::mofo:
depends on what you can do yourself and how much you pay someone to do your work.....

$300 - $500 gets you the headers and mid section (cats)
figure $200 for a 2 into 1 muffler and some welding from a local shop
set of 6.1 SRT8 springs, install and .030 mill = $350
2 new head gaskets + new head bolts, new header bolts = $200
cam = $450
srt8 crank pulley and new crank bolt (always change these crank bolts) = $150
Diablo Pred Tuner = ??????
Tune = ?????

I figure about $1700 + tuner and tune

Wait for me to do it first and do a write up and then you can figure out if you want to do it.
sounds sweet unfortunatly I have the 4.7 liter. Should have got the hemi
 

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I'd be very interested in trying to pull 300-350 BHP out of a 4.7. Not sure if it's even possible for under $5k.
 

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i need to take a closer look to the intake and head design. The cam work should be easy. Another issue is dealing with off-th-shelf headers already available.

With the HEMI you get a platform that has an awesome intake (manifold), a cyl head that is top notch, the ability to buy used 6.1 headers and mid pipes, existing cams and tunability.

I'll take a closer look at the 4.7

I believe alot of our answers are on the Dodge truck sights
 
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