Building a lock up 727 or a stubby 47rh?

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PRINCETON_JAKE

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I need a SHORT transmission for my monster/off road project. I'm running a 5.9 common rail and have several core tracnsmisions to build/play with.

Can a 727 be built to lock up? I have searched everywhere and can't find answers of anyone who has actually done it. Can I use a 47rh valve body and triple disc converter?

I was hoping to just swap tail housings but that clearly won't work.

If I can't build a lock up 727 how can I mate a 727 to a common rail? Can I make a thinner 1st gen adapter plate work?

Here's a picture of my first attempt with a 12 valve and Allison. I need to fit the drivetrain, and profab monster case down bellow the top of the 4 link bars
 

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A 1st gen block plate may work on a commonrail, but 2 bolt holes will be totally different, it'll bolt up with 6 out of the 8, just 1 hole on each side will be in the air.
Fortunately, the dowel holes DO line up and have bolts through them.

You'll also need a 1st gen starter and you'll need to make something work to seal the rear of the cam on the commonrail.

In the late '70s and the '80s there were some 318s and 360s built with 727s that had manual (pressure) lock ups.
I'm not sure if the pump, input and valve body from those years will work in a Cummins 727 case, or not.

There are also some 727 applications into the '90s in vans with a 3 speed auto that may have a lock up function.

Mark.
 
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Thanks mark, I was aware of the cam issue, but did not know the bolt difference. I do have the 1st gen plate, starter, and flex plate.

I'm curious if anyone else chimes in with help on making it a lock up.
 
There's a small shop local to me that builds alot of mud trucks with 12valves, they tried using lockup at first but now run tight convertors without due to breaking alot. Similar to what your doing, tube frame, scs trans case, 2.5 ton rockwells, tractor tires.
 
In fact I think they started just using 727's, I may be wrong but I'll ask if you want. The guys shop is D&G custom golf carts (Dave), he's built a bunch of high end trucks like yours, Jacksonville Fl. Good guy that I'm sure would give you any advise, his trucks run strong and work.
 
I was worried about having lock up being to stressful on parts, especially jumping and landing with the tires spinning. I need to find out how to mate the 727 to the. I'm in rail.

For what it's worth I plan on putting the spare mock up motor into my driver and the 1260hp motor from that into the mud truck. I have 5 ton axles but I know they are not going to hold. Unfortunely I sold my 20 ton planetaries before I planned on going this far. I have 20.8-38 rice and canes and 66x43 terra/monster tires
 
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