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Discussion Starter #1
Hi all

I’m researching a conversion for my Series 3 SWB Landrover and was directed to this very helpful and informative forum.

I have begun to read up on some similar projects and discussions relating to Landrover conversions but I’ve noticed that most owners seem to retain the original drive train and just exchange the combustion engine for an electric motor.

I can understand this if the owner wishes to retain the off-road 4WD capabilities of the vehicle but for others like myself who would be happy to convert the vehicle to 2WD using the rear axle only (as some Dutch military Landrovers were), is there an option to take the drive from the motor directly to the rear axle via a driveshaft? Providing of course that there is sufficient clearance past the various crossmembers for the drive shaft to run.

One other alternative could be front wheel drive using the front axle with the reversed motor offset slightly in the engine bay to align with the front diff but I’ve not got that far with my research yet.

If not and the existing gearbox and transfer box is mated to the motor, does the gear change then become ‘clutch less’ and require the vehicle to be brought to a stop in order to select a gear to cope with different gradients and hills in the traditional manner?

Any feedback on these basic principles would be appreciated.
 

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I can understand this if the owner wishes to retain the off-road 4WD capabilities of the vehicle but for others like myself who would be happy to convert the vehicle to 2WD using the rear axle only (as some Dutch military Landrovers were), is there an option to take the drive from the motor directly to the rear axle via a driveshaft? Providing of course that there is sufficient clearance past the various crossmembers for the drive shaft to run.
The only challenge is that, unlike most 4X4 vehicles, Land Rovers place the shaft to the rear axle in line with the shaft to the front axle, instead of down the centre line of the vehicle. That means that if the electric motor is placed where the transmission normally is, there are three alternatives:
  1. run the shaft at a significant angle (probably not a good idea)
  2. replace the rear axle with one that has the differential in the middle (an extra expense)
  3. use a gearbox which offsets the output from the input, the way the transfer case does (and you can even just use the transfer case, and keep 4WD)
If you need some reduction gearing anyway (to match the axle input speed to a desirable motor speed), you could use one of the reduction gearboxes that various electric truck conversions have used... if you can find one.

If not and the existing gearbox and transfer box is mated to the motor, does the gear change then become ‘clutch less’ and require the vehicle to be brought to a stop in order to select a gear to cope with different gradients and hills in the traditional manner?
Shifting without a clutch is possible without stopping, but it is slow and hard on the transmission's synchros, due to the rotational inertia of the motor. It could be quick and easy, if only motor controllers were programmed to change the motor speed to match the shift; that could easily be done, but it's not in the programming of OEM controllers because they have single-speed transmissions, and it's not in the programming of aftermarket controllers because they're just not designed with this feature.
 

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Thanks for the reply and information.

I suppose the driveshaft offset issue could be overcome if the motor was to be placed in line with the diff flange so perhaps mounting the motor where the transfer box is mid-vehicle as opposed to using the engine bay and using a shorter drive shaft.

For a direct drive arrangement like this is some form of gearing still required or is it possible to source a motor that will allow the vehicle to be driven under all normal road conditions i.e. about town, motorway and steep gradients without a gearbox interface?

If I’ve understood some of the threads correctly, there will be a number of different motors that I could look at that will be suitable (in terms of output and physical dimensions) for this vehicle. After that I need to define what sort of range I would want from it and charging rate and this will allow the number and type of batteries to be calculated. Is that how it works or am I approaching this the wrong way?

Once I understand the basic principles of EVs then I’ll be able to develop the idea further and come back with more detailed information to assist with the responses but appreciate the help so far.
 

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Hi BigJ,
I have just joined the forum after being a reader for quite a while, and yesterday jumped in a and bought a '72 mini moke, I did consider a Defender/Series LR myself but though I should start on something smaller and lighter.
I'm a Defender guy myself (110 double cab) so I can certain see the appeal, but I was thinking more like a Chevy LS3 -in my dreams.

If you were happy to go with 2WD it would certainly be much simpler, cheaper and lighter Project...and in reality how often does anyone need 4WD in the UK...want yes, need ..not really.

I'm not 100% sure but I thinks it is possible to run a 2 motor set up with motor speed encoders and linking the motor controllers/Inverters via CANbus, you could then directly or indirectly connect each motor to each dif for a 4WD set up, but thats pretty advanced stuff for 1st time build- too much for me and I'm an electrical engineer.

Good luck and keep us posted
 

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I'm not 100% sure but I thinks it is possible to run a 2 motor set up with motor speed encoders and linking the motor controllers/Inverters via CANbus, you could then directly or indirectly connect each motor to each dif for a 4WD set up, but thats pretty advanced stuff for 1st time build- too much for me and I'm an electrical engineer.
Yes, that works, and it is how every AWD (4WD) production EV is built - one motor (or two) per axle, coordinated by computer. No manufacturer would seriously consider driving both front and rear axles from a single electric motor, but it does make sense for a do-it-yourself conversion of a vehicle that already has a mechanical 4WD system.
 
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