H42-np205 doubler/adapter (1 Viewer)

[69LC]

And so it begins.

Last fall I bought an engine and 4-spd from a 78 fj40. Then I bought a couple of fj60 h42 OP shafts from Georg and a Dodge np231 23-spl, wide bearing Input gear.

I just got the sun gear back from a local guy who does EDM for his day job and at home as well.

Now things can move forward!

NP 205 drive flanges and which CVs to use?

Hey guys. I need to get back to my build on my 40 and am trying to determine what to use for CVs and drive flanges on my 205. I have some early mini truck CVs, but don’t feel like they will be up to transferring power from a healthy LS 6.0 and 38s. If it can be done inexpensively, what are...

forum.ih8mud.com

np 205 mods

i've been given the green light to build my 40. I will have to do a bunch of custom axle work, finish my custom tranny/tcase adapters and lots of other stuff, but I'm starting with the NP205. It's a late 70's GM 8-bolt "racetrack" version. I have a complete Ford case that will be donating most...

forum.ih8mud.com

 

[cruisermatt]

Hold on,
you're going straight from H42 to 205? Interesting.

 

[matzell]

looks like a 231/241 input maybe then a blackbox or something to the 205?

 

[69LC]

I’m building my own planetary doubler to act as the tcase adapter.

This is what the old splines looked like.

 

[cruisermatt]

oh hell yeah.

 

[matzell]

So are you taking a 27 spline NP241 input and changing the input splines to fit the H42? Then making an adapter plate to bolt to the back of the H42? Looks like it will be a "custom" blackbox type thing without an extra adapter plate. Keep at it, I am interested to see where this goes.

 

[69LC]

It was a dodge np231 23 spline sun gear-Wide bearing. There was just enough material to EDM cut the fj60 h42 19-spline into and have full splines and still be in the heat treat area. The nice thing about the EDM process unlike rebroaching is that the heat treat didn’t need to be removed and reapplied. I currently have about $200 into buying the gear and have it cut. I paid a local spline machine shop a half gallon of Grey Goose to draw up the splines using the op shaft and the split case PTO gear. My EDM buddy now has the adjusted file.

yes, it’s basically a home spun “black box”.

I’m going to rely heavily on my engineering student son to get the dimensions I determine drawn for case fab/machining.

 

[69LC]

The next major task will be to mash the 231 op shaft and np205 ip gear to be as short as possible. I may find a double row bearing for the front of the 205 to carry the extra load and eliminate the need for extra case length.

 

[cruisermatt]

Great project. Besides cost (I'm assuming you have a hookup on machining and materials to make this worthwhile) what would the advantage be over the blackbox? Length?

 

[69LC]

I can do it myself and it will be shorter overall.

 

[cruisermatt]

going in a 40, right?

 

[69LC]

Yessir. It will have a shaved and narrowed C&C 14B rear and hybrid Ford 9”/80 knuckled front.

 

[AJR]

 

[69LC]

Save your popcorn. It’s going to be at least a few months. Wasn’t practical to bring parts along on deployment to measure and draw from.

 

[Lated]

Save your popcorn. It’s going to be at least a few months. Wasn’t practical to bring parts along on deployment to measure and draw from.

Pffft! There are plenty of cruisers in the sand box to play with.

 

[69LC]

Yeah, there seem to be a lot of 79 series and some 100s, but nothing with the np231 planetary that the recut sungear is going into. The rumor mill is saying anywhere from 5-7 weeks for heading home.

 

[Lated]

Yeah, there seem to be a lot of 79 series and some 100s, but nothing with the np231 planetary that the recut sungear is going into. The rumor mill is saying anywhere from 5-7 weeks for heading home.

True enough. I wish I could have brought a 70 series or two home with me.

 

[GLTHFJ60]

Subscribed.

 

[69LC]

I just got a present from the brown truck! Got my 60-series h42 top plate.

My Downey conversion bellhousing arrived while I was tdy. Now that I’m home I have to work faster on the great big honey do list. Then 40 work.

 

[Lated]

That packaging is awesome