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Offset Tie Rod Kit From RuffStuff!Ruffstuff Axle Simple Swap Kit!ROCKRIDGE4WD Introduces a NEW Jeep Wrangler JK *led* tail

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Unread 10-12-2011, 12:28 PM   #16
youngjeeper11
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No questions or comments?

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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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Unread 10-12-2011, 02:51 PM   #17
goldeaglejeep
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This is a fantastic swap I hope to under take some time in the future. I put it on the back burner for a while to focus on school work but I plan to start slowly collecting parts to get it rolling. Your thread is a huge inspiration! So the 12v Dodge transmission bolted right up or was there an adapter that needed to be fabbed up?
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Unread 10-12-2011, 05:27 PM   #18
cherokeekid12
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Great job on the swap. I also did this swap in an 88 YJ with a th400 trans. I want to put an intercooler on mine and am curious as to which size cooler you used. 400 ft/lbs will be easy to reach without compromising the engines reliability. I hope to get mine on the dyno soon to see what it can do, so far I have just installed a fuel pin and 3200rpm gov spring.
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Unread 10-13-2011, 05:56 AM   #19
youngjeeper11
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thanks! I still have some bugs to work out.

The dodge stuff does indeed bolt directly up. From what I gather the 4BT is the same block a the 6BT 12v, minus 2 cylinders, and a few differences in the lubrication system. There is a diference between the cummins engines and what you would expect on a typical V8. There is not a round "bellhousing" shaped bolt pattern cast into the block, but 8 holes, that are in 2 angles rows (4 holes on each side) on the back of the block. There are a number of adapter plates that will bolt to the block, there are ford, chevy and dodge versions of this adapter plate, some are clocked 10 degrees as well. If you get all the components from a 12v dodge ram, pre-97, (after 97 they switched to the 24v, actually at like 98.5 they switched to the 24v) from adapter plate, bellhousing, flywheel....ect ect, it all bolts up, no adapters.

I am curious as to what numbers you hit on the dyno with just the fuel pin and 3200 rpm srpings! Did you have an adapter plate that was clocked 10 deg for the th400? I will try to find the intercooler again on ebay. Most my research on intercoolers came up with hte same answer, use the biggest intercooler you can fit, So I found one that fit, but did not take up the whole grill.
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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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Unread 10-13-2011, 06:54 AM   #20
tankinyj
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no glow plugs on this engine? what does it use then just compression? did you go with 3.08's because the power from the motor is enough to make up the undergearing? what size tires are you running with these 3.08's? did you stick with the stock D35 (god i hope not)
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Unread 10-13-2011, 10:05 AM   #21
youngjeeper11
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Correct, No Glow plugs. Just starts with compression, glow plugs are only utilized on diesels engine to make starting easier, but I suppose they just never had starting issues. I know the 6BT has glow plugs. The 6BT also had an intake grid heater, and I have seen people adapt this grid heater to the 4BT intake, and basically its a small electric grid heater that heats up the intake air during starting to make starting easier. I have not had to try to start it in the cold yet so we will see, but it also has a block heater on it.

I did not re-gear yet. I plan to go with 3.08s mainly because the engine will not go over 2800 RPM without modification, and the maximum speed this engine can safely achieve is 3200RPM and right now with 3.73s(I think, I have never took the time to look) and 30" tires, the engine is pinned at about 2700 rpm going 70 mph down the highway.

So to compare it to a gasoline engine, imagine driving down the high at 70MPH at 5000RPM...in 5th gear...... your not in the power curve of the engine, and your not running very efficient.

This engine makes its power between 2000-2500 rpm give or take. Therefore my goal is to be right around 2000RPM at 70 mph, where the engine will be most efficient.

And yes, the amount of torque makes up for the low gearing easily, I can pull out from a slow roll in 4th no problem.

Also, with the turbo, you want the gearing to be in sync with when the turbo is building boost. Its hard to explain without driving it and feeling it, but Right now, if I am in 2nd, I can only go like 20 mph, and its not even a load on the engine, so it does not build much boost. The only time it builds significant boost right now is in 5th gear.

I guess the best way to explain it is, go put your jeep in 4lo and try to drive down the highway haha, thats what its like driving my jeep.

So, currently yes it is a Dana 35, I have yet to decide if I just want to put in a Ford 8.8 with 3.08s, or if I want to do dana 44s. The Ford 8.8 is cheap, easy, and most people say pretty strong, but I blew one to pieces with my old Jeep that had a Chevy 350, so I am no longer sold on the idea of an 8.8.
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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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Unread 10-13-2011, 10:36 AM   #22
ninjakid
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Awesome job there.
I might have missed it but what's the mileage on the original body you used and your beastly engine?
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Unread 10-13-2011, 11:25 AM   #23
oldtime_ironman
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Given that you have a 4BT, I would at least consider a D60 rear. Also, since yer into engineering and stuff, you *really* might want to check out MBRP's build thread... they used a 6BT and crazy mods. Linky here:
http://www.jeepforum.com/forum/f22/m...ersion-1155821
.
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Unread 10-13-2011, 11:34 AM   #24
youngjeeper11
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I have no idea the mielage on the frame or body, the engine has like 70K since a re-man, so it should be good for another....300k haha
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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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Unread 10-13-2011, 11:38 AM   #25
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old time- I saw that thing when they were just starting it, and I toooootallllyy forgot about it! It is a very very impressive piece of work, I love it, just once I would love to build something where money is not an issue, not saying that those guys are just blowing money, but their pockets are much deeper than mine! haha
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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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Unread 10-13-2011, 11:58 AM   #26
oldtime_ironman
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Quote:
Originally Posted by youngjeeper11 View Post
old time- I saw that thing when they were just starting it, and I toooootallllyy forgot about it! It is a very very impressive piece of work, I love it, just once I would love to build something where money is not an issue, not saying that those guys are just blowing money, but their pockets are much deeper than mine! haha
Yah, I would love to build something crazy again... I used to do crazy stuff on chevy full-sizes before I got into jeeps. You should check out where their build is at now, its seriously impressive engineering... gotta remember tho that they have their whole company backing it up, that's the money thing.

And seriously I'm amazed you haven't blown up your drivetrain yet. Seriously, get a 14-bolt or something in your rear, you can find them everywhere for cheap.
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Unread 10-13-2011, 12:39 PM   #27
youngjeeper11
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Yea, I hope to get an engineering job at some jeep parts company eventually, working at Novak was awesome, and Utah is amazing, but my family is on the east coast.

I am confident I could put it in 4wd, spool it up and dump the clutch and grenade both axles at the same time haha. I need to do more of my own research before I decide what axles I want. I am in no real hurry. It runs and drives. I am most likely to break it down shifting. The tires will chirp downshifing from 4th to 3rd haha. And as of now, I'm working on it in a parking lot, with no way of getting power to it. So I am limited to "bolt on work" can't do much fab, and Its not really seeing much of trails.....life is getting in the way
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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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Unread 10-13-2011, 01:12 PM   #28
youngjeeper11
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I was looking for more pictures, because I knew I some of taking the trans apart and puting the adapter on and more of the actual assembly of the driveline, but I realized they were on my camera that was in the front seat of the jeep when it caught fire....
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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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Unread 10-13-2011, 01:29 PM   #29
kb3mtv
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First off, awesome and clean swap dude, I'm really jealous lol
But the killer dowel pin is actually a really bad thing. It is a dowel pin used to align your timing cover to the block that can work itself loose and destroy your engine. You can buy a kit to secure it and its not too hard to do.
To bump up your fuel there is a fuel plate on your injection pump that you can cut to allow more fuel and more soot
Good luck with everything and enjoy the best diesel engine money can buy
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Unread 10-13-2011, 01:51 PM   #30
youngjeeper11
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hmm, you are probably correct about the dowel pin, I am sure there is a safe way to do it as it seems common, as far as the plate, are you sure? The injection pump is the older one, I think its known as the "VE 44" or something like that, I don't remember, I just want to make sure your not talking about the fuel plate on the 12v injection pump that you can loosen, slide forward, then turn a little "star wheel" to get more fuel and smoke.

I used to have a 95 12v that I had a #0 fuel plate in, and boy did that thing ever have balls, and it could leave a nice thick cloud of soot haha.

I love Cummins haha, I was at the state fair over the weekend, and there is always those sticker stands that have all kinds of red neck stickers for your redneck truck, I almost bought the "real trucks dont have spark plugs" sticker.

I asked the guy if he could make me one that said "Jeep makes it, Cummins shakes it" and he just looked really confused....
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Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college
Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project
Interned at Novak Conversions 2 summers ago

Ask me about my 4BT Cummins Motor Mounts!!
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