TJ Exhaust headpipe into XJ?

Hey Guys, I think this is my first post on the forum. I am on here fairly often but I usually find the answer to my question with a quick search. Not so this time.

I have a 98 XJ, that I just finished an engine swap. I just replaced the 4.0 with a 4.0 out of my brother's 98 TJ (hope he doesn't notice :eeks1 The engine swap couldn't have gone any smoother. Everything was plug and play! While I was in there, I saw the bend in the head pipe and thought that it was dammage. I have read that this is a factory deal, but I would still like to replace the head pipe anyways.

Once again I got some hand me down parts from my brother. He was going to use his TJ as a donor for a buggy, but he has since rethought that. So he has been very generous, giving me parts to use or sell. (He gave me his 40" MTR's on H2 wheels and a high pinion 8 lug Dana 44 front end just to name a few things) Among other things he also gave me a nice stainless mandrel bent head pipe (for a TJ). Before I threw it on CList, i did some searching and I discovered that TJ headpipes are a popular swap onto YJ's. The YJ headpipe hangs way down underneath the tranny and I guess everyone bashes them on the rocks.

http://www.virtualjeepclub.com/showthread.php?t=9091

Then I thought "oh :smsoap:" my exhaust goes down under the tranny. (I am new to wheeling, but not to mechanical type things, did cars and motorcycles before) So all this beating around the bush leads to my question. Can I use the TJ downpipe I already have, on the engine that came out of the TJ but now lives in my XJ? As with anything I am sure there will be complications, but I would love to hear if anyone has done it before or tried and failed because ___? Thanks Much,

Hellooooo.....? Anybody? Care to speculate....

If you can use the header from the old engine on the new one you should be able to use the exhaust from the old one. I believe the header collectors point in different directions.

I think I've seen some pics on here of people who have routed it around the front. Check the clearance of the pipe under the oil pan and the axle while the axle is flexing. Almost looks like the YJ front axle is further forward than the XJ (don't know, not familiar with them.) The front XJ axle is right under that end of the pan so unless you've got enough lift and bumpstop you could hit the pipe into the pan with the axle.

seems like you'd also throw a lot of heat (more than normal) at the oil pan and starter unless you heat wrapped the pipe.


The XJ exhaust seems like it's tucked up pretty well, enough so that it's not a big issue area for most people to do anything about.

Looking at our TJ, it seems that clearance between the front axle and oil pan would be an issue using that style of exhaust on an XJ at stock height or with minimal lift. Don't know if you are intending to run the 40's you mentioned but at that point, it should no longer be an issue.

I had to replace the cat on my 2.5l tj, and it came with a new down pipe. The downpipe was only for the 4.0, so i had it leftover and tried to fit it on my XJ. i have 4.5" of lift, and there is no way i was getting it in there. Even with the lift it would have been crushed as I went down the curb at the end of my driveway. If I recall correctly, I also would have had to pull the front axle just to get it in there because of the way it was bent. I couldnt figure out a way to make it work easily so I gave up, and will be cutting it up and using the bends to make a custom one. Someone really needs to start making and selling an aftermarket one.
Lightfoot

Forgot to mention, it was a 2.5" downpipe

Bummer, that sucks. I'm running 32's on 5.25" of lift and the downpipe is 2.25 but it doesn't sound like that is enough difference to even come close. Maybe I will do the same, cut it and re-use the bends. Thanks!

The motor in a TJ (and YJ) is further back in relation to the front axle then on the XJ. Stick with the cross under pipe on the XJ.