The last month has been a lot of reading, taking notes, researching and making plans. Last Saturday, after club breakfast, I got busy pulling the 351










351W vs R2.8







I also started a pile in the basement for all the Cummins swap parts.



Now I'm getting busy on that transmission adapter.

Wow I envy your knowledge on fitting that motor in the engine bay, I wouldn't even know where to begin.
Looking forward to the progress!

For having half the liters, it's amazing how big that motor still is!

Wow, that is great side by side shot, I didn’t expect the motor to be so symmetrically square. My 4BT is more tall than wide, I’ll have to dig up the dimensions so we can compare them.

I had a few people comment on size difference, so I threw the intake and induction back on the 5.8 and used MS Paint to bring the two engines level with each other for relative size comparison.




The Explorer front dress and induction system is more compact, but you get the idea.

Wow! It is hard to believe that there is little size difference between the 2. The pic with the engines on the floor make the diesel look huge.

Can't wait to see the progression.

Made a little more progress. I've been busy measuring and modelling for the transmission adapter. Axis Industries has a few of these and frankly, they've distilled their design down pretty well. My first attempt looked way too much like their's. So much so, I considered trying to contact them again to discuss this project. BUT I had an idea today that simplifies the adapter and gets it away from looking like a copy.


First thing I had to do was mock up the business end of the Windsor block and make sure crank and bell housing dimensions were correct. Then I mated that to a section of the R2.8 and starting hashing out how to mate the two. This is the end result:

Here's the whole setup with a very quick and dirty transmission package.
CAD Mockup 01.jpg


Adapter with Ford flywheel
CAD Mockup 02.jpg


Without flywheel
CAD Mockup 03.jpg


Exploded View
CAD Mockup 04.jpg


I need to have a template LASER cut at work to confirm all the hole placements. After that, we'll be making chips.

Digger,
Your build make me feel like I'm working with poster board & large crayons

ok, so the red part is the r2.8 and then the default SW colored part is your adapter? I am pickin' up what you're layin' down!

remind us again, you are sticking with a ZF5 correct?

Gotcha. Such an awesome setup it will be!!

How many parts will the adapter be? I assume one for the flywheel as well?

Time for update.

This adapter has consumed a lot of time in order to get it correct the first time. I felt the dimensions for the Cummins side of the adapter were pretty solid, but the dimensions for the Windsor block side of the adapter came mostly from the internet and we all know how reliable the internet is. Particularly, one dimension for the transmission bolt hole was different depending on the source. I needed to verify hole positions as best as possible before proceeding. I created a sheet metal part that contained all the holes from both sides of the adapter plus a pilot hole to align the input shaft to and had it cut out at work.

I fit it to both ZF5s and the R2.8 and confirmed holes at least looked correct. Several holes have spacing that needs to be accurate to within a thousandth of an inch or so, which is hard to verify accurately. The other holes could be +/- 0.10".





The mounting hole in question looks well centered based on the dimension I assumed was correct, but there is enough slop in this hole it likely doesn't matter.

While waiting on a few items, I dropped the gas tank to see what the inside was coated with. Diesel apparently dissolves zinc finishes and redeposits them in the engine. Not good. Unfortunately there is some type of coating on the inside that looks very zinc-like. I will have to clean and seal the inside of this tank before proceeding. I found some other things I didn't like after removing the access cover. There was left over parts from assembly and weld slag floating around the bottom of the tank. Additionally the feed line is undersized and the return just shoots out the top of the tank, which can aerate the fuel. I will have to address these things as well.






Looks like pre-plated sheet metal. Note the return line is just a fitting welded to the side of the tank.



The baffles look decent

Since the fuel system is getting rearranged, I will have to run new hard lines. Wanting to do things a little nicer than last time, I'm upgrading to stainless for brakes and fuel. I decided to order a roll of tubing instead of straight pieces to eliminate any fittings along the frame rail.

This tube straightener is much bigger than I thought.


The roll of 3/8" tube is HUGE





After some additional CAD modelling, it became clear the stock engine mounts will not work. They are too far rearward in the engine bay. I could get the engine mounted but the stock mounts prevent the Cummins starter from being removed without pulling the engine. So those have to go.




Annnnnd gone.

Getting back to the adapter...

I spoke with our manufacturing engineer at work in order to get a recommendation on a machine shop. (our shop is busy most of the time) He looked at my project and thought we could fit it into the schedule, so we had some back and forth discussing how to produce my bell housing adapter, what machine should run it, who would program it and what was critical. I went ahead and purchased the raw material, a 50lb slab of 6061-T651 aluminum plate that measured 18"x18"x1.5"




After about 4 weeks, it was time to run my part. The guys really did a great job. It was run in a horizontal mill with a pallet changer and a 35HP spindle. It made short work of my plate.



The final product is beautiful and dead accurate. The guys CMMd the part and the critical dowel pins holes were all within 0.0002" of their nominal positions. The dowel holes were reamed, so press fit will be very precise.

With the bellhousing adapter finished, I needed turn the 10mm dowel pins down slightly. Given that the holes in the engine were reamed, I didn't have the right measuring tool to accurately measure the ID to 0.0001". So I ordered standard +tolerance dowel pins and test fit them. They almost wanted to go, but not quite. Because the dowels locate the engine to adapter to transmission, I couldn't just chuck them in the 3-jaw and turn them with cutting tools. I needed something more precise. Generally when you're working under 0.001", you need to grind, not cut, so I rigged up a makeshift tool post grinder with a Dremel tool. I also loaded the 4-jaw chuck and dialed the dowel pin to the lathe so there was less than 0.0001" runout.




I ended up taking off 0.0004" over 4 passes of the grinder.




You can barely tell anything was done, but the upper 14mm of the dowel is a smaller OD.




Now the pins slides in easy, but is still tight enough to seal the air behind it.




After grinding a lead-in chamfer, I pressed all 4 dowels into place.

Now for the moment of truth...
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Perfect!




The fit on the engine side was so perfect and tight, I had to slide the adapter in very squarely or it could get stuck, but lined up right, it just slid right on.





I also checked the starter clearance. Just enough.

While the guys at work were machining the bellhousing adapter, I was at home working on the crank adapter. I already had to redesign this once after sourcing material proved to be difficult. Now it's a little smaller. The crank adapter proved to be a challenge to manage all the tolerance stackup over all the features of two adapters plus flywheel etc. After giving some thought to the manufacturing approach, I got started.

Starting out with raw stock...



...I faced the part (after dialing it into the lathe), punched the center bore which located the 2nd crank adapter, and turned the counterbore that locates the adapter to the crank. Tolerances for the critical features were all sub-thousandth of an inch. I was aiming for 0.0003 or less deviation from print.




Turning the hub face for the starter ring




A-side completed.



And test fitted

Now things starting getting frustrating. I spent the first 5 hours of the 2nd day trying to get the part dialed back into the lathe. After trying a few different configurations and switching measuring tools, I got it as close as possible. After reading the factory calibration report, I am at the limits of what this lathe can do.




After finishing the B-side and measuring runout, I moved the part to the mill to punch all the holes.





More holes




And counterbores




What a mess.




After tapping all the holes, the finished product



Checking bolt fitment vs the model





Finally, checking fit on the engine

Just Wow!

you have gone . love it

Great work, you make it look easy!

Unbelievable.

Very nice!
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