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Discussion Starter · #1 ·
Okay so I know that the 4bt and scout IIs go great together and will bump up the mileage as well as the drivability. I have purchased a bread van that has a 4bt in it and plan to swap it into my frame off restoration scout. The bread van has the t19 transmission in it currently but as I'm sure you all know they are not 4x4 and what is a scout without 4x4? My question is what transmission/bellhousing/transfercase set-up is my best and most cost efficient choice? This is my first time with a motor swap and don't really know what I' looking for other than drivability. help sheading light on this topic for me would be greatly appreciated! I will be needing to figure out this issue in the upcoming few months. Thanks!
 

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What does your Scout have in it right now? No doubt there are adapters to Ford or GM smallblock V8s. And 4BTs can be found with adapters that have the same architecture of either engine. You need to know what you have before we can offer advice on what your options are.
 

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Discussion Starter · #3 ·
I have the IH 727 tranny that was behind the factory motor along with(I believe) the Dana 300 tcase. But I bery well could be wrong but I believe I have read that the ih 727 is different than the 727s that they put in dodge trucks... But that is what I have in my possession! Can always sell/trade my way to different parts though!
 

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With a dana 300 on one end, and a 4bt on the other, you have LOTS of options. The question you need to ask is what are you going to use the Scout for, that will point to the best tranny option. Then weigh that against your budget...
 

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Discussion Starter · #5 ·
The scout will be used as an occasional daily driver but not constantly as I have a dodge cummins I will daily drive. The scout will be used occasionally off road but mainly on the road as something cool and different to drive around in! Love turning heads in something custom that I built with my own two hands! With some good advice to make it all happen lol
 

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I had a scout setup with T 19 trans and married transfer case that had a SAE 3 circular clutch housing on it . May have been factory option for that diesel IH used .
 

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The scout will be used as an occasional daily driver but not constantly as I have a dodge cummins I will daily drive. The scout will be used occasionally off road but mainly on the road as something cool and different to drive around in! Love turning heads in something custom that I built with my own two hands! With some good advice to make it all happen lol
Well, if you want both highway speeds and good offroad ratios, it will pretty much require an od of some sort. Assuming you want a manual, the easiest option to mate to the 300 would be an nv4500.
 

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Discussion Starter · #8 ·
Okay so if I went the nv4500 route what would I need as far as bell housings adapters and and all of that good stuff? Would the nv4500 bolt straight up to my 4bt?
 

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Discussion Starter · #9 ·
Also what would be some good automatic options as well? Really wouldn't mind either way just have to make something work with the clutch as my scout was factory automatic.
 

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I have the IH 727 tranny that was behind the factory motor along with(I believe) the Dana 300 tcase. But I bery well could be wrong but I believe I have read that the ih 727 is different than the 727s that they put in dodge trucks... But that is what I have in my possession! Can always sell/trade my way to different parts though!
The IH bellhousing pattern does NOT fit any other brand engine.

Are you CERTAIN that you have a Dana 300 tcase? They were only used at the end of Scout II production, in some 1979 and in 1980. It is not unusual to have newer parts in an older Scout... Ours now has the 392 CID engine swapped in it.

Also verify the tcase to trans flange pattern. If my memory is working, IH used a "Texas" pattern and Jeep used a round pattern.

You "might" be able to use a Dodge/Cummins 727 transmission and bolt on the IH tail housing and transfer case. I am not certain of the details, our Scout had an almost fresh engine, so the 4BT went into a light pickup truck.

You need to figure out if this is a trail and local runabout vehicle or a long trip vehicle. You will need overdrive for highway and interstate traveling. It will be very difficult fitting overdrive and a transfer case in a 100 inch wheelbase Scout II. The rear drive shaft is VERY short. If you have the longer 118 inch wheelbase, life is easier...

Go to the Grimjeeper web site and run your axle ratios and tire sizes on their calculator.

http://www.grimmjeeper.com/gears.html
 

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Discussion Starter · #11 ·
From what your saying my transfer case may not be a Dana 300 as it is a 1973.. And as for overdrive that would definitely be nice as I'm sure it will see it's fair share of highway miles back and fourth to different places.
 

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From what your saying my transfer case may not be a Dana 300 as it is a 1973.. And as for overdrive that would definitely be nice as I'm sure it will see it's fair share of highway miles back and fourth to different places.
You need to carefully document what you have installed. Many old IH trucks and Scouts have various repairs and parts swaps performed on them, in order to keep them running (and not spend a lot of money).

Determine your axle ratio (verify both axles if you do not know the history of your scout).

Record your tire size

Go to the Grimjeeper calculator and run the numbers - Remember a 4BT is most efficient between 1600 and 2000 RPM My Ford, in the signature below, turns about 2080 at 75 MPH.

p.s. Remember the 727 does NOT have a lockup torque converter. High gear will be somewhat less than a 1:1 ratio.
 

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Discussion Starter · #13 ·
The rears have 3.73 gears the front I'm not sure bc it's a different axle (Dana 44) but will most likely just run the same gears! And from what I've seen in pictures doing more research on my t case it is a Dana 20.
 

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The rears have 3.73 gears the front I'm not sure bc it's a different axle (Dana 44) but will most likely just run the same gears! And from what I've seen in pictures doing more research on my t case it is a Dana 20.
3.73 and a Dana 20 tcase sounds right for a stock 1973. Our scout gets 9 to 10 MPG running local errands, more like 11 MPG on interstate trips (75 MPH out here). It vapor locks in the heat when we go to Tucson and Phoenix. We now only drive it locally, at least once a week - a trip to town is 20 to 30 miles. I've never settled on a good trans/tcase for a diesel conversion...
 

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Discussion Starter · #15 ·
That right there is why I decided to buy the 4bt because I'm hoping to get like 15-20 mpg and not have problems in heat or cold to much. The 4bt is much more powerful and reliable than the 345 I had but just like you there are so many options I just have no idea where to start and what the best rout is. I kinda like the nv4500 idea but it will be fairly costly to me as I'm running out of funds for the project. And on top of that would have to make a clutch setup for mine sense it was factory auto. Just trying to see what everyone here has for ideas!
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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3.73 gears with the NV4500 and 33" tires is a great combo for all around drivability. Go with a Dodge 518/46RH for a automatic option (same gears) or step up to the 47RH with a lockup torque converter for even better mpg. All of these combos will net you milage of low 20's in town and high 20's on the highway.
You could also put in a Getrag G360 5 speed out of a first gen Dodge coupled with a NP205 for doing it on the cheap.
Be sure to source your Dodge trans from a Dodge that had the Diesel option or they won't connect to the trans adapter.
 

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Discussion Starter · #17 ·
What adapters will I need to bolt up to my 4bt for the nv4500 and what transfer case would be best? How hard would it be to stick with my Dana 20 I already have? Thanks!
 

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On www.justih.org there is a guy (user name Coreysmith) that has done a few 4BT swaps into the Scout-II. IIRC, he has posted some builds on that forum. Would definitely be worth checking out. From what I remember, his work seemed to be good. From his posts he definitely seems like a sharp, and straight shooter.
Hth,

Scott
 

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Discussion Starter · #19 ·
Thanks for the link! He has some great pictures and info on that blog on doing the swap but doesn't have a lot of info on my trans and transfer case options! But as for the swap it self very helpful! thanks!
 

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What adapters will I need to bolt up to my 4bt for the nv4500 and what transfer case would be best? How hard would it be to stick with my Dana 20 I already have? Thanks!
Don't know if the IH D20 is kin to the Jeep or Ford units but the adapters are out there!! The prices of them just to keep a D20 makes most just step up and run the NP205s for less money and a much stronger TC! For the GM NV4500 get the GM adapter parts but you'll be stuck with the smaller flywheel/clutch or you can get all Dodge adapter parts and then convert the nose of your GM nv4500 to the Dodge style architecture. It's only money either way you want to play! It has ALL been done before you just have to search out which way you want to proceed and read what others have done and the pitfalls they've conquered so you can hopefully avoid them.


http://www.advanceadapters.com/prod...wd-to-jeep-dana-20-transfer-case-adapter-kit/
 
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