Cummins YJ

[Fredduck]

And so the mock up begins.  Just to give you some history: I bought my 88 Yj last summer for some light off roading, well that didn't take long to explode into something else. I found the 3.9 -4 cylinder cummins turbo diesel with a chevy transmission adaptor. The reason I've decided to go with the diesel was my buddy and I make bio diesel. So then I found a 700R4 tranny, a Dana 44 front axle, a Ford 9" and a NP 241C. So there are the ingredients. I've been taking photos throughout the dismantle and mock up stages.I wnet with the Bronco coil spring front end and that change over was very straight forward and surprisingly easy.  I still have to build motor mounts and A new skid plate / belly pan just to finish the mock up. After the mock up, I will have to sand blast and paint the rolling chassis. As the diesel hasn't got a vacuum pump I have to find a hydroboost brake booster.
I've attached some links to the tear down and mock up.
http://photoshare.shaw.ca/view/11816366873-1199025724-89511/
http://photoshare.shaw.ca/view/11816332984-1200099355-16319/

[dunl]

You know, once you're finished, you're not going to want to drive that thing.

poor guy....tell your wife i chatted with mine, and it was a hard sell, but she's willing to let me take it off your hands (once it's all finished you know.....) 






Sweet rig.

[Fredduck]

If I die I hope she doesn't sell it for What I told her I have into it

[i_go_commando]

some of the astro vans have a nice compact hydroboost setup. easier to find than one off a pickup. thats what im gonna swap into the fc170 for power brakes

keith

ps nice job. ive seen those adpater on ebay, and ive been thinkin instead of a continetal 6 a cummings would be nice, and the military fcs were diesel powered....

[Fredduck]

The CUMMINS 4Bt has roughly the same HP as a stock Jeep 6cyl but way more torque. about 240 to 300 FT/LB. It's a couple hundred pounds heavier and is about 6 to 8 inches shorter so the next challenge will be to fab motor mounts so the engine isn't too top heavy but also doesn't sit too low. the injectors are interchangable between the 12 valve cummins (first gen mopar) and the 4BT so more power is available with pump timing and fuel pressure.Some of the adaptors on Ebay are very expensive but they are set up so the engine doesn't have a tilt. The GM piece tilts the engine 10 degrees, this has no effect on the engine. I've been told you can tilt the engine or the tranny but if you tilt the tranny it lowers the transfercase and that aint good. On kijiji Edmonton there is a shop selling rebuilt cummins 4 cylinders for about $4000.00.
The 6 cyl Cummins is such a large engine I don't think it would fit in a "stock" jeep but it would be fun to try; Cummins, 6speed manual, Atlas, Dana 60's 5.13's lockers 4o inch tires HMMMM... 
I'm gittin itchy waiting for my fabricator to show up

[cLAY]

The GM piece tilts the engine 10 degrees, this has no effect on the engine. I've been told you can tilt the engine or the tranny but if you tilt the tranny it lowers the transfercase and that aint good.

Was this a lube issue or a driveshaft issue? Most jeeps have CVs on the front shaft and can take a lot of angle. I had a 2" t-case drop on my XJ and the output of the front was actually pointed up a slight bit and have no vibes and I ran it on the highway in full time 4wd all the time.

[Fredduck]

This is more of a clearance issue. I'm installing the NP241-C and right now she is hanging a little low. The engine tilt I was talking about was the left to right tilt not front to rear. Although with the short distance between the transfer case and the rear diff drive shaft angle will play a part in deciding how much higher I lift the tail end of the drive shaft. I've ordered JB conversions super short shaft slip yoke eliminator for the NP241 so that will add drive shaft lenght. Has anyone heard of a double cardan drive shaft?, a cv joint at each end.