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Discussion Starter #1
Hi

Has anyone done a motor direct connect to driveshaft conversion? What adapters or solutions did you come up with, or anyone know of any examples? I need to go directly from the motor to the driveshaft. Any help be appreciated.

Thanks
 

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Discussion Starter #3
Cool build Duncan,

What im looking to do is mount the electric motor up front in engine bay area where the old gas engine and transmission lived. Connecting it to the original drive shaft to the original diff in the rear. Im looking for ideas on how to mate the electric motor shaft to the yoke on the drive shaft.
 

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Yes - that is effectively what I did - but the motor takes the place of the transmission - leaving the whole "engine bay" for batteries

The adapter is a simple disc with holes tapped at 8mm and a machined ring on each side to keep the two parts concentric
 

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Discussion Starter #5
Yes, that's what I need except I have keyed shaft on my motor. I need to figure out how to go from that to a yoke at the other end.

How did you do reverse?
 

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Reverse is easy - just use a reversing contactor

I used one off an old forklift - a small 24v one - but I did oveload it at the last drag races so I bought a bigger one

You will need need an adapter for your shaft - I'm NOT in favout of driving through the key you will need the taper lock type of adaptor

https://www.youtube.com/watch?v=fT4axK3haQ0

Next
the drive shaft - a two UJ type shaft needs to have some end movement - some axial movement
My car has that with movement of the female spline part on the male spline

Any type of clamping lock on a keyed driveshaft will NOT have any axial movement - so you will need the axial movement in the propshaft

A lot of (most?) car propshafts do have an axial sliding joint as part of the propshaft
 

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So the taper lock joint would take the place of a splined slip yoke to provide axial movement?
No - the taper lock would have zero movement - but most propshafts have a sliding joint as part of the propshaft


https://bearmach.com/propshaft-br-0404

The propshaft on this page has a sliding joint

Some propshafts don't have a sliding joint because the gearbox output has it built in
 

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Discussion Starter #9
My brain hurts now...lol...So the original transmission had a male splined shaft and the drive shaft had a female splined piece that fit into it...This is a 54 Ford...So Im having issues of how to mate this key shaft electric motor into it...This is my first attempt into doing an electric conversion and trying to figure out to combine the modern to the old:confused:
 

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OK first treat the propshaft as "parts"

The diff end will be a flange with four bolts

You need to get hold of another propshaft so that you have got the splined bit and both ends
That page I linked to was for landrovers (I think) but all sorts of machinery from the 50's to the 80's had propshafts and I'm pretty sure there are only a couple of sizes

Then forget about that bit until you have the adapter on your driveshaft and the motor bolted into the car

Now you need to measure how long a propshaft you need and take all your bits and that measurement to a local machine shop - they will cut and weld you a new propshaft

Here (NZ) I needed to get it balanced and to have some metal around it in case it broke
 

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My brain hurts now...lol...So the original transmission had a male splined shaft and the drive shaft had a female splined piece that fit into it...This is a 54 Ford...So Im having issues of how to mate this key shaft electric motor into it...This is my first attempt into doing an electric conversion and trying to figure out to combine the modern to the old
The female splined end of the original 1954 Ford prop shaft was probably free to slide on the male splined end of the transmission's output shaft. Since your motor does not have a splined shaft, you can
- use something like the TransWarP setup (splined shaft and bearing in a housing), or
- just attach a splined end to the motor shaft (probably not structurally sound), or
- attach a U-joint yoke to the motor and use a shaft which has a sliding section in it (the ability to slide is called "plunge").

There are a lot more than two standard sizes of propeller shaft components, and few modern cars have a sliding (plunging) feature in a propeller shaft. Fortunately companies which specialize in supplying these components and fabricating shafts to connect the parts that you have, often with "driveline" in their names.
 

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Discussion Starter #12
So, What about if I got a coupler that mated the keyed shaft on one side and a six inch section of the output shaft from the original transmission? This would be able to slip into the original driveshaft. Would it be an issue strength wise being this length? Also, would it be an issue of the output shaft being in the slip yoke without the collar that was on the transmission tail piece?
 

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So, What about if I got a coupler that mated the keyed shaft on one side and a six inch section of the output shaft from the original transmission? This would be able to slip into the original driveshaft. Would it be an issue strength wise being this length? Also, would it be an issue of the output shaft being in the slip yoke without the collar that was on the transmission tail piece?
Your problem with that is ensuring that it was well enough mounted to the motor driveshaft - it would need to be very rigid to avoid it whipping

I would prefer the driveshaft with the "plunging" joint in it -
 

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Discussion Starter #17
Ok, so there is travel in the middle. So this is a full drive shaft or a segment piece to complete the length from my motor to the existing drive shaft. Please bear with me if Im asking stupid questions, this is the area of the build I'm confused with
 

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OK that's an example - you may be able to just buy one the right length - or move your motor back or forwards until the length works out

Otherwise you would get a machine shop to cut and weld - you can see both ends of my driveshaft in the last picture - it's only about a foot long

Using an "off the shelf" one has a lot of advantages

In your shoes I would -
first look at your transmission tunnel -
is it large enough for your motor?
- can you make it large enough?
That sets where the motor can live

take your existing propshaft and offer it up - that will show how long a shaft you need and what size UJ you need to go onto the diff

Then go to your parts supplier and talk to him
Most older cars had propshafts, today BMW and Subaru and various trucks have propshafts

Find what there is - if you are lucky you can buy a new one or get one from a scrapyard

Don't forget the space needed for the adapter that goes on the drive shaft
 

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So, What about if I got a coupler that mated the keyed shaft on one side and a six inch section of the output shaft from the original transmission? This would be able to slip into the original driveshaft. Would it be an issue strength wise being this length?
Your problem with that is ensuring that it was well enough mounted to the motor driveshaft - it would need to be very rigid to avoid it whipping

I would prefer the driveshaft with the "plunging" joint in it -
I agree with Duncan. That's why I listed this alternative as "probably not structurally sound" earlier.

Also, would it be an issue of the output shaft being in the slip yoke without the collar that was on the transmission tail piece?
The usual tailshaft housing surrounds the sliding bit of female splined shaft, as a protective cover; the equivalent sliding section in a shaft typically has a rubber boot. Yes, protecting the sliding section from getting dirt in it is an issue.

So this is a full drive shaft or a segment piece to complete the length from my motor to the existing drive shaft.
... you may be able to just buy one the right length - or move your motor back or forwards until the length works out
Many long trucks have multi-part propeller shafts, with a joint and steady bearing and support bracket at each connection between shafts. This shouldn't be necessary in a car, especially if you can put the motor back in the transmission tunnel, but many current cars do use two-part prop shafts.

Using an "off the shelf" one has a lot of advantages
...
Most older cars had propshafts, today BMW and Subaru and various trucks have propshafts

Find what there is - if you are lucky you can buy a new one or get one from a scrapyard

Don't forget the space needed for the adapter that goes on the drive shaft
Anything with an engine and transmission in the front, and driven rear wheels, will have a propeller shaft (so yes, almost all BMWs and pickup trucks are examples); however, many won't have a sliding part of the shaft, either because they use a sliding spline at the transmission output shaft (like the '54 Ford), or because they use constant velocity joints (instead of U-joints) which allow plunge, just like the axle shafts used with independent suspensions.

A live beam axle (such as in this 1954 Ford) will typically require more shaft length change than an independent rear suspension (in which the final drive unit basically stays stationary). With IRS, the shaft might even get away with the slight length change allowed by guibo couplings, but you wouldn't want to depend on that with a beam axle.

In a quick search, it does appear that BMW tends to use shafts with a sliding section. Here in Canada it's hard to imagine a more expensive source of parts than German luxury-performance auto manufacturers, but of course this varies by location.

All-wheel-drive vehicles will have a propeller shaft (except for electric vehicles, and hybrid vehicles with electric-only drive to the axle at the other end from the engine); however, that shaft may not be designed to handle a lot of power.
 

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Discussion Starter #20
diff 1.jpg

diff 2.jpg

motor.jpg

motor 2.jpg

Heres what Im looking at to mate, I am mounting motor in transmission tunnel but it leaves a gap of 10 inches from end of slip yoke and the face of the motor
 
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