6bt into '94 fzj 80 idea

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Sep 27, 2005
Hood River, OR
What do you guys think of swapping a 12v cummins into an 80 and retaining the stock drivetrain? The idea is do make an adapter that is similar to the Mark's V8 adapter. Basically one adapter for to bolt the toyota flex plate to cummins flex plate and then another to mate the cummins bellhousing to the toyota tranny. I have heard that the A442F is a fairly stout tranny and with an upgraded valve body and maybe a different torque converter it *could* handle a 6bt in stock form. I am fairly limited in my knowledge of auto tranny tunning so I know I need to do research there but does anyone see any flaws in this setup? Because I have a '94 the tranny has a seperate TCM which I a not sure if it use/needs a signal from the ECM or if it basis the shifting on the VSS and the TPS. Anyway I am far from diving into this but I wanted to see what others might have to say.
Should be a nice swap .. I'm in love forever with Cummins engines ..

2 issues pop from my mind about this swap.

1. The oil pan in a 6BT it's deep .. you must have a 6" lift or so to deal with this .. ( maybe less with a modified oil pan .. )

2. The Extreme valvle body from Rodney in Australia could handle that power .. ? just need to ask he.

At the A442F the tranny could funtion without all other sensors without problem, a new valvle and relay setup to match the shifting points ( rpm ) from a low end torque engine as the 6BT should be diferent than any gasser ..

The weight of the engine it's for sure another issue to keep in mind .. less problems on that.

Good luck and keep us posted.
Dave George has a 6BT in a FJ62 and was running the stock auto tranny behind it. His 6BT is the early non-intercooled version (I think he has propane inj.) He said the tranny did fine but started to get too hot pulling his boat (ocean boat) so he just put in the NV4500, seems very happy with that. Of course, running a big-rig diesel shop he machined up all the stuff to make the 440f work but I believe bought an adapter for the 5 speed. You can search his name and I think you'll find the post here on mud. I checked it out. Very functional.. didn't have much room for the exhaust tho'.
Yeah I think for sure the exhaust routing would be fun (judging by how much room there is in my 60 with a 4bt, although the exhaust is not started yet...). The adapters I can make easily enough b/c I work part time in the machine shop at school and we have some fancy machines. I was hoping to retain the tranny/t-case just because I like the toyota stuff and I already have it, it all works well together, etc. I would probably go with a toyota diesel but they are pretty pricey to get one here and well....cummins makes some sweet motors. I will definitely call Rodney if this project gets a foundation and get all the info on setting up the tranny. To me it just sounds like a good combo, the 6bt is a smoother running motor then the 4bt, it has plenty of power in stock form, they are everywhere, parts are easy to find.... guess I'm just thinking out loud and looking for some encouragement.
As far as the required lift to clear the oil pan - couldn't he go w/ a 4in lift and fab up a hood scoop? I'm sure there could be some visability issues while on the trail, but it could then allow him to go w/ a cheaper lift.
As far as the required lift to clear the oil pan - couldn't he go w/ a 4in lift and fab up a hood scoop? I'm sure there could be some visability issues while on the trail, but it could then allow him to go w/ a cheaper lift.

Hood scoop would work but I'm already running the slee 6in lift so at least for me clearance wouldn't be an issue.

Forgive me if you've already seen this, but it has been a work in progress for awhile.


Yeah I have seen/been following that thread (although it has been pretty slow over the last couple months/year), I think his build is going to pretty sweet but not really what I am going for. It seems to me that the Toyota running gear will hold up to the 6bt if it is kept in stock config., which is how I would leave it. Sure it would be nice to crank the fuel pin and spew smoke and snap axles and whatever else... but for me I would be doing it to gain some mileage, some power, cool factor, and retain reliability.

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