Exhaust manifold replacement

Hi all!

I've known for a while that my POS (piece of ...) original exhaust mainfold on my 4.0 had cracked. It's leaking where all of yours are (or will) and I'm looking at replacing it.

How big of a job is it? I imagine I'll have have to pull the intake off too, and replace the gasket. Do any of you know of online instructions or specs for doing the job?

Thanks!

This might help
http://www.go.jeep-xj.info/HowtoExhuast.htm

May I suggest a better remedy to the cracking exhaust manifold? BANKS Manifolds are the BOMB! I put one in a CJ-7, I had to remove the intake manifold, the kit came with everything I needed, all stainless,and is wareentied never to crack. Besides it sounds great.

May I suggest a better remedy to the cracking exhaust manifold? BANKS Manifolds are the BOMB! I put one in a CJ-7, I had to remove the intake manifold, the kit came with everything I needed, all stainless,and is wareentied never to crack. Besides it sounds great.
Much agreed. Just did one on my XJ a while back. Easy job, took me 2.5 hours with decent hand tools. The Exhaust/Intake manifold bolts on the bottom of the manifolds are a little tough to get to, but you can wrangle your hand up in there from underneath the jeep without too much hassle.
Hopefully whatever header you buy will come with the neccesary gasket. May I also suggest Banks. You will spend just as much for a factory peice that is just going to crack again in 40k miles, as you will for a high quality stainless steel, better performing header. Borla, Gibson, and Pacesetter all make a replacement/upgrade as well. And they are priced in that order. Not so ironically, so is their quality.

Just curious, what kind of performance did you gain from the Banks headers? And if you don't mind, about how much do they cost? I'm thinking of upgrading mine, and have heard great things about Banks. That Aussi from Go-jeep-xj.com gives a good nod to Banks, too.

I think I've decided on the Banks myself, just need to convince my wife that the exhaust system fix is more important than new carpet...

Tell the wife that if you dont fix that exhaust, you wont have anything to bring home the carpet in.
A bad manifold will NOT pass smog, as cherokees are notorious for this. With a vehicle that is not legal to operate, she'll think twice about the luxury of new carpeting... and how to get it home.

The Banks ran me about 450. That can vary about 50 bucks depending on the retailer you go through. Performance wise, I gained a noticeable seat of the pants pull from about 2500-3500 rpm, a bit quicker throttle response, and a pleasing throaty burble at idle and high range RPM. I also have accomplished about every bolt on Modification produced for a 4.0 shy of forced induction, and was running them with a mostly stock exhaust. So I assume it was a very welcomed addition to my engine, hence the noticeable improvement.

Hey Artic, have you tried the #19 injector swap yet?

Hey, Arctic, thanks for the response. I had a feeling that would be about the price. If it's [Banks] as good as everyone says, then it sounds reasonable. I'd like to do more motor mods myself...and getting that rich sound would be nice. What's the rest of the exhaust mods?

Carlson

High flow CAT, Banks muffler w/ Tailpipe. Random Technologies makes a good direct fit. Also look into a K&N filter kit, maybe upgrade your ignition system.

Hi GT,

when you say upgrade ignition system, what are you referring to? Coil, wires?

Also, I see Rocky-Road.com has Thorley headers, the price looks like abt $360 shipped and the design looks good. Has anybody installed these?

The biggest thing to look at is the header flange. Thorley may be good to, but I know for certian that the Banks system (header, CAT Back system) is, what I feel the ultimate in exhaust systems. Compare the grade of stainless, you might find others are using a lower grade.
Yes, I meant coil, wires, plugs, maybe even the distributor itself if you can afford it. These items get expensive, but worth it. I ran a MSD Blaster II on my 71 Ford, Awesome!

i have a header from a 2000 laying in my garage...looks almost new let me know if you are interested

Hey Artic, have you tried the #19 injector swap yet?
You know, Ive been considering that for a while now. For the life of me I cannot remember the site that I went to, but they had a whole selection of Bosch fues injectors from 15# and up. IIRC, they had 17, 19, 22, and 24lb ones too, all compatible with the 4.0. I was gonna try out the 22lb ones first, and if they were to much flow, I'd sell them to a friend of mine running a stroker and 5.0 ford injectors, then pick up the 19s.

Im gonna go spec hunting tomorrow on the net and look up the part numpber on the 19# ones that will work with the XJ, and then dig around to find out what other vehicles used these as OEM. When I find out, i'll be heading out to the local junkyards to find a set.

High flow CAT, Banks muffler w/ Tailpipe. Random Technologies makes a good direct fit. Also look into a K&N filter kit, maybe upgrade your ignition system.
In addition to these, a larger diameter down pipe would be quite an improvement. Sadly though, nobody produces one for the Cherokee 4.0. If you are in with your local exhaust shop, see how much they'll charge you to bend up a custom down pipe, with a bung for the O2 sensor. Might be a bit pricey, but those damn OEM downpipes are insanely restrictive.

Hi all!

I've known for a while that my POS (piece of ...) original exhaust mainfold on my 4.0 had cracked. It's leaking where all of yours are (or will) and I'm looking at replacing it.

How big of a job is it? I imagine I'll have have to pull the intake off too, and replace the gasket. Do any of you know of online instructions or specs for doing the job?

Thanks!
I cant quite remember what all i had to take apart, but it wasnt that much even for a shade tree mechanic. But i took my exhaust manifold off and had it welded, put it back on and is still working fine so far as of about 4 months. I didnt have the 600.00 for a jeep manifold.