oem hardware: adapter plates, couplers, axles, etc

[Bratitude]

The amount of development around open software (and electrical hardware) for a variety of oem parts is astounding!

But as the software side nears plug and play, I think hardware side should too.

I want to extend these efforts into the hardware realm:


-universal adapter plates
-gearbox stub shafts and flanges
-replacement gear sets
-motor couplers

Leaf parts are a favourite around here, and for good reason. cheap, powerful, and easily hack-able.
software side, driving leaf components is fairly flushed out, and nearly plug and play.

now on to hardware:
I'm mainly focused on leaf parts at the moment, but creating a repo of designs for a variety of gearboxes and motors would be ideal.




Adapter plates:

em57 adapter plate with NEMA B-face bolt pattern cad files: https://github.com/angusjo/adapter-plate

depending on the gearbox your adapting to, some additional backing spacing might be required, simply add some B-face patterned shims.

Im planing on machining a batch of these em57 adapter plates. Trying to hit a price of under 300$ cad each. If your interested, let me know.


Over time, building up a public repository of different gearbox bellhousing bolt patterns would really simplify and streamline the conversion process for many folks. If you know of any sources for gearbox bolt patterns, please let me know.





Gearbox stub shafts and flanges:
The leaf gearbox is a small, and strong gearbox. Though its not often it's utilized in conversions.
This for most part, appears to be the issue of cv axles.

me and janik have been discussing about cv stub flanges.
we've started developing a set of stub shafts flanges for the leaf gearbox.

they are going to be a 2 part assembly, this is to increase use case and reduce manufacturing cost.

1: the stub shaft has leaf splines on one end, and 25 spline Subaru on the other.
2: the flange will be a female 25 Subaru spline with a 108mm and 100mm cv joint bolt pattern.

vw type 2 use the 100mm and porsch 930 use 108mm style axle flanges. these bolt patterns are used on virtually all European vehicles. With plenty of material available to machine in custom patterns if required. flanges like these are already available from suppliers like http://www.subarugears.com/

The gearbox has a offset diff in relation to the motor, resulting in different leaf axle joint lengths, accompanied with a bearing support. for simplicity and cost, the bearing support and longer axle joint wont be utilized. One replacement stub shaft design will be used for both sides of the gearbox.



replacement gear set:
changing the 8:1(ish) reduction to something closer to 4:1 would allow the leaf gear box to be used as a replacement for transfer case in 4x4/awd vehicles.

this would require a change to the first and second reduction gears to a 1:1 ratio.
looks like 2 bespok replacement parts are needed: a new splined reduction gear, and a new input shaft with matting outer splines.

[Jack Bauer]

That's brilliant work!

[Robert]

replacement gear set:
changing the 8:1(ish) reduction to something closer to 4:1 would allow the leaf gear box to be used as a replacement for transfer case in 4x4/awd vehicles.

this would require a change to the first and second reduction gears to a 1:1 ratio.
looks like 2 bespok replacement parts are needed: a new splined reduction gear, and a new input shaft with matting outer splines.

While you're in there, can you design a spool to positively connect the "front" and "rear" driveshafts together?

[Bratitude]

While you're in there, can you design a spool to positively connect the "front" and "rear" driveshafts together?

Nismo makes LSDs for the leaf gearboxes already, but yes I would like to talk with quaife about a atb or a spool

[Tremelune]

Nismo makes LSDs for the leaf gearboxes already

Interesting...Do you think this would help with straight-line acceleration? My Mini is FWD and it reeeally struggles to get torque to the ground from a stop.

[Robert]

Nismo makes LSDs for the leaf gearboxes already

Interesting...Do you think this would help with straight-line acceleration? My Mini is FWD and it reeeally struggles to get torque to the ground from a stop.

The Nismo LSD is a helical gear type LSD. It would be great in your Mini but not for a rock crawler type setup. Torque sensing differentials require at least "some" resistance at both outputs and if you completely lose traction on one wheel (or one driveshaft in my example) you lose all your output power.

This link gives a good description of the issue

https://www.kmpdrivetrain.com/different ... ferential/

[Bratitude]

https://openinverter.org/wiki/Leaf_gear_box

Link to nismo lsd https://www.nismo.co.jp/products/nismo_ ... 19.html#a2


The trouble is ordering one from nismo Japan. I know it’s been done, but unsure how to get some for redistribution

[Bratitude]

some updates if any one is following:

Gen 2 leaf motor (em57) adapter plates with NEMA B-face bolt pattern are entering production!
Looks like I’m hitting cost targets bang on! they should be available for 330$ cad soon. Ye haw!

A coupler customer reached out and sent me a em57 gear box! So thank you for that!
then found a pair of clean axles for free!

So I’ve been busy taking measurements and doing to math for the involuted splines. Already into printed prototypes for the replacement stub shafts!

As janik found, the seals on ether side of the gearbox are different, but interchangeable (interns of fitment on the gearbox) so a seal swap on one side and stubs should be good to go.

[Bratitude]

First mock up print of the stub flange assembly.
Just enough room!
tight between the flange and the motor, but ample room for a 108mm/930CV joint

[Bratitude]

updates:

-Machine shops are busy, and but things are trucking along. But the Gen2+ leaf motor adapter plates are coming soon.

-any one interested in some flanges for mounting hdt sprockets on the Hyundai HSG motors?

the shaft is 22mm diameter with a 4mm wooduff key. It’s non-standard keyway, so custom flanges are needed.

again looking at making something some what universal.
They would be machined potentially out of aluminum, and have a bushing style taper + bolt pattern to fit a variety of hdt sprockets

[Bratitude]

em57 universal adapter plate drawing

[Tremelune]

Well that's lovely. Has one been installed in a driving car yet?

[Bratitude]

Well that's lovely. Has one been installed in a driving car yet?

Cheers.

not this revision with the NEMA B-face pattern, but the older design, which has the exact same mounting position for the leaf side, is in use in as variety of vehicles

[Bratitude]

finally leaf adapter plates are in. available in the web shop. https://bratindustries.net/product/em57-adapter-plate/

I’ve been working on the stub shafts for the gearbox. They have gone through quite a few iterations. Again around the goal of making them easy, inexpensive and universal. what I’ve landed on is a leaf-to-33 spline VW stub shaft.

There are 3 different flanges available from many different suppliers for this vw spline: type 1(90mm), type 2/4 (100mm) and the 930 (108mm)

Using 930 flanges and joints will require shaving the motor casing, as they are just so big. even then, they might not fit.

the last final detail I’m working on is the seals. My original plan was to use the original leaf axle seal. this would result in a flange distance greater than what is on the original vw transaxle.
To Mitigate the odd flange spacing, the design could utilize the VW flange seal surface.
luckily there is a seal that fits both the leaf box and the vw flanges: OD 56mm and 36mm ID

using the flange seal surface will allow a tighter fitment, and will match the spacing of the flanges on a original vw trans axle.

[Bratitude]

some updates;

stub shafts are in final phase. off to production soon!

adapter plate kits for old vw beetle/bus transmissions and nissan 5speeds.
intermediate bolt pattern is all nema b-face.
next is machine mockups, verify fitment, then off to production!

[VWJoe]

Good work on the adapter plates, just checking a couple of bits on the VW plate. The two lower fixings on a VW gearbox are studs, is there enough clearance to allow for these. Also, the standard engine is not aligned by the bolts, but by a small lip on the engine ( now adapter plate) that goes into the bell housing. Is this present as I can not see it on the drawings. Hope this helps

[Bratitude]

the standard engine is not aligned by the bolts, but by a small lip on the engine ( now adapter plate) that goes into the bell housing.

Yup! That is present. The first screenshot shows a lip on the plate.

[VWJoe]

Good to hear, hope the testing goes well.

[motorcircus]

Any news on the Nissan leaf to VW axle stub adapters? Will they be available June or will I have to find another solution?

[Bratitude]

Any news on the Nissan leaf to VW axle stub adapters? Will they be available June or will I have to find another solution?

they are just entering the productions stages as we speak! no word yet on when ill have them, tho should not be long!

[Bratitude]

few updates:

vw-to-leaf stub shafts will be available begging of October maybe sooner. Beautiful cold rolled 4140 chromoly steel. yup cold rolled, oem spec, 4140, race spec!

vw transaxle adapter plates will be available in 6 weeks or so. end of august.

nissan 5mt gearbox adapter plates are available now. cad files on github. mates with any nema b-face motor

I did a write up on making a motor coupler. this applies to anyone doing anything with clutch splines.
https://bratindustries.net/how-to-mate- ... r-coupler/

[llopness]

Are the gear sets available or still in a development stage? I saw them on your website but there was no price or ability to add to cart.

I'm not aware of anything besides the Toyota Land Cruiser that has both front and rear driveshafts colinear with a right hand drop.

Would it make more sense to adapt the motor directly to a transfercase and just use low gear?
some maths on gear reductions
leaf 7.95(2011-12) 8.3(2013-?) : 1 stock 25" tires 6405/6695 RPM @ 60MPH
TLC transfercase 2.49 * 4.3 axle ratio = 10.71:1 stock 31" tires 6967 RPM @ 60MPH
Leaf axle with replaced gear (75/17?=4.41) * 4.3 = 18.97 stock 31" tires 12341 RPM @ 60MPH

[Tremelune]

Interesting...One issue I can think of with using a transfer case is that it's likely designed to spin to 6k rpm, and not so much the 10k the Leaf will do...Might be a worthwhile trade-off, depending on your goals.

[Bratitude]

Vw adapter plates !
Subaru ea81 adapter plates!

the NEMA B-face assembly approach really shines through with how much cheaper it is to get an bespoke adapter.

Just finished measuring the Outlander rear motor, onto the em61 (gen 1 leaf) next. Then NEMA adapter plates for those motors aswell!

[Bratitude]

Leaf em61 and outlander rear motor adapter plates cad files on GitHub. Currently Untested. https://github.com/bratindustries/adapter-plates