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Cummins into an XJ... This will take a year.

MoparManiac said:
I bought some 1.5" plain steel exhaust tubing from Summit Racing(straight pieces and U-bends).

Butt welded them and used rubber hose for any joints (I wanted certain sections to be removeable for servicing other parts of the jeep). Wherever the rubber met the tubing, I ran a small weld bead around the edge of the tubing to act as a catch for the hose clamps. Works perfect. I also added a drain point at the lowest point of tubing and some bleeders in the engine bay to assist with getting rid of air bubbles.

Looking back it would have been nice to TIG the tubing since I could have forseen any leaks from the start. Had to fix one area that was a PITA.
Click to expand...

That sounds like a really good set up. It's too bad marmon clamps probably aren't water tight...

MoparManiac said:
I'm sure people thought my drivetrain would be too heavy (Probably tipping the scales at just over 1k lbs) but I haven't had an issue with it.

400+ HP and 500 + lb-ft of torque makes it feel light as a feather :D
Click to expand...

Word.

I should have some pics up this weekend... It's been raining for the past 3 weeks here but it finally looks like sunshine.
 
MoparManiac said:
I wasn't talking about his power.

But I wouldn't be dropping in a 4BT expecting massive HP.

Would be a fun trail rig engine.
Click to expand...

no....it'd be a nice commuting motor. One can get 30 mpg on 33s or something nutty like that.

On the trail, it'd be painful. :lecture:
 
I was waiting for the haters to come out of the woodwork!

QSBpowercurve_zps8105a5a4.jpg


...ish.

cracker said:
You won't get that HP out of that motor....
Click to expand...

I know that, silly. I'm going for low end torque.

cracker said:
no....it'd be a nice commuting motor. One can get 30 mpg on 33s or something nutty like that.

On the trail, it'd be painful. :lecture:
Click to expand...

California won't let me put that motor on the street. This engine was designed to go in one of those mini-bulldozers, backhoes, trams, etc.

jeeperjohn said:
What about using a short powerglide tranny? Are you married to manual?
Click to expand...

Yeah, I am set on going manual in this build but thank you. :)
 
Unfortunately, I don't. There's a "new" one for almost $10k on eBay...
The older ISB 3.9 is a truely badass little engine, though, they aren't that hard to come by, and they're mechanically injected. They can be had complete for around $3k-3500. Those aren't that loud, really. I'll let you know how loud this one is when I start her up! Electronically controlled diesel engines are a lot quieter.
What I think would also be a really cool engine for an XJ swap is a Detriot Diesel 3-53. It's a 3 cylinder 2 stroke engine that they put in the Gama Goat. Some of them are aluminum too.
 
I have been dreaming about putting a 4bt in a MJ for a long time... :dreamin:

inspiration for your build: http://youtu.be/R1sq7PIvPO0
 
This looks like it'll be awesome. Can't wait to see what you do with it.

cracker - aren't 4BTs super tall? One of the guys up in my neck of the woods ("Goat" on here IIRC) put one in his XJ and he said he had to lift it a few inches just to maintain clearance on the front axle, iirc. Not sure how far he's gotten with his build, we talked a bit about it in fall 2010 when I was up at Johnny's place helping him build a shed and took a break to meet up and drop some parts off for Goat's build.
 
kastein said:
This looks like it'll be awesome. Can't wait to see what you do with it.

cracker - aren't 4BTs super tall? One of the guys up in my neck of the woods ("Goat" on here IIRC) put one in his XJ and he said he had to lift it a few inches just to maintain clearance on the front axle, iirc. Not sure how far he's gotten with his build, we talked a bit about it in fall 2010 when I was up at Johnny's place helping him build a shed and took a break to meet up and drop some parts off for Goat's build.
Click to expand...

Yep, it's super tall. It's gonna be a PITA making mounts for it.
 
I finished my twin stick conversion on my NP 205 on Friday, but I haven't had time to post pics until now. I used this article:
http://www.jpmagazine.com/techarticles/drivetrain/154_0008_np205_twin_stick_shifter/viewall.html
On mine, though I had to modify both the range shift rail and the front shift rail in order to get it to shift into FWD High.

I lined my range shift rail up just like they JP did, marked, and cut.
20121207_135626_zps4569acf5.jpg


I reinstalled the rail, but it wouldn't shift into FWD in either gear, so I used paint to see which interlock pin I was hitting.
20121214_142920_zps9fd0403e.jpg
 
I cut some more, and ended up with this:
20121214_134409_zpsa527aa98.jpg

JP's write up doesn't show the side view, but once you realize that you have to allow the pin to move half the width of the shift collar, you can take off the right amount.
After that, I still couldn't get it to shift into FWD High. I realized that it was blocked by the back of the front shaft. Mine looked like this; I don;t know whether they had a different model or what.
20121214_152815_zps5eb9267f.jpg
 
I moved it to allow the shaft to move forward just far enough to engage the front synchro, but not far enough to allow the range rail to move backwards in this position.
20121214_153504.jpg

After this, I checked it again and threw it back together. It has all the ranges it should, and none that it shouldn't.
Unfortunately, Transtar sold me the wrong gasket and seals kit, (after three tries..but at least I have the right bearings), so I had to buy different output shaft seals since mine are 32 spline all the way around. I found them at NAPA, so I can put the covers on tomorrow.
Another problem is that I will have to look for a different gear for my PTO. My PTO came from a Ford NP 205, and the drive gear doesn't mesh to my 205. I ought to be able to just change the gear... the depth looks correct...
 
kastein said:
This looks like it'll be awesome. Can't wait to see what you do with it.

cracker - aren't 4BTs super tall? One of the guys up in my neck of the woods ("Goat" on here IIRC) put one in his XJ and he said he had to lift it a few inches just to maintain clearance on the front axle, iirc. Not sure how far he's gotten with his build, we talked a bit about it in fall 2010 when I was up at Johnny's place helping him build a shed and took a break to meet up and drop some parts off for Goat's build.
Click to expand...

yeah, it is STUPID tall. Most of the guys modify the piss out of the oil pan for maximum clearance.
 
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