I am currently rebuilding/modifying a 68' J200, i have considered alot of different engine & driveline upgrades , nearly went AMC 401 , but recently saw a good second hand Cummins 4BTA ( 3.9 ltr Turbo diesel )which had a  T700R4 mounted to it .

I was wondering if anyone has a done a conversion with this motor or seen any , how did it go , know of any power upgrades to it ( Turbo , intercooler, propane injection , etc ) ????   Also i saw one article in a JP magazine and can't remeber which one it was ( a year or 2 ago ) does anyone know what month/year it was ?

Have a wicked day - from an Aussie Jeeper

Rick

I imagine it wouldn't take too muck to crank the 3.9 way past the tourque limit of the 700r4. I'd think a smallish turbo from a pickup deisel, a pickup intercooler and some bigger injectors (probably uses the same injectors as the 5.9) would do lots for it

that engine will be fairly tall too (same as the 5.8), so you might need a body lift to use it

you reckn the TH700R4  won't be able to cope with a modified 4BTA , do you know what those trannys are max rated at ?  I saw a good second hand ZF 5 speed O/D  gearbox & T/case out of a 02-03 -  F350  really cheap  from an engine importer ( aussie land ), might get  that and get a flywheel & clutch  to suit it.

Thinking i will freshn this 4BTA  to handle substantial power upgrade  Cryogenic treated bottom end &  calico or HPC coated to handle it all , planning on running large hi-flow intercooler & efficient ball bearing turbo & propane injection . 

Hey how do you upload pictures of your project on here  , maybe even in JP magazine ????  ( probably be heaps of people asking this )

the 4 should be 2/3 the 6 it stands to reason. the 6 can be made to have 600ft-lbs pretty easy. from the sounds of your planning, you'll exceed 400 in your downsized model. you could build the 700 to take that, but I doubt it yould live long stock.