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Discussion Starter · #1 ·
My grandfather and I have started a project converting his 1980 Volkswagen Rabbit Cabriolet to electric. So far all we have is the small front drive unit out of a Tesla Model X. We don't know a whole lot on how to continue but that is why I'm here.
 

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If you intend to put a Model X drive unit in the front of a Rabbit (or any typical transverse-engine car), you should be aware that it won't fit in the intended orientation. You might find the experience of 4G63T in his Mitsubishi relevant: see post #7 of The Evolution of My Evolution.
 

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Discussion Starter · #3 ·
If you intend to put a Model X drive unit in the front of a Rabbit (or any typical transverse-engine car), you should be aware that it won't fit in the intended orientation. You might find the experience of 4G63T in his Mitsubishi relevant: see post #7 of The Evolution of My Evolution.
Oh yeah I have watched a few videos of this car!
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wow I guess I never realized that it sat behind the drive axles in the car. I wonder if the gearbox would handle highway speeds in what would essentially be reverse if the motor was mounted backwards. I'm assuming that would be less than ideal. Alternatively would mounting the motor upside down cause issues?
 

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Inside the drive unit is a gear driven oil pump. I believe the inclination tolerance is around 10 degrees each direction, so mounting it upside down is not an option. Maybe it might work in the correct orientation for your car. I would strongly suggest to do really good homework on fitment for your application before committing to it.

I was ok with running in reverse. But doing so took up more engine bay space verses using a small rear drive unit. Which i still have to install and run in reverse lol.

I hope this photo and data is helpful, source from Zero EV. Unfortunate for me i found this way after buying everything.
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If you do decide to mount it in reverse orientation, the oil pump will not work as intended. It will still spin but flow direction reverses. So inlet for the oil pump becomes outlet and vise versa for the outlet. You can either open it up and try swapping the lines or run an external pump. Refer to this thread Tesla Small Drive Unit Mounting

Zero EV sells reverse oil pump for the large rear drive unit. But i believe small and large drive units oil pumps are not interchangeable.
 

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Maybe it might work in the correct orientation for your car.
I doubt there's much chance of that, but the dimensioned drawings certainly help. It looks like about 400 mm from front axle line to firewall would be needed, plus bracket allowance and clearance, or slightly less with some forward tilt.

The VW Golf (such as this Rabbit) is the prototype of the modern transverse powertrain layout, and like all examples of this design (including the Mitsubishi Lancer) the engine and transmission sit ahead of the axle line and so the firewall to front axle distance is as short as possible (given wheel well intrusion into the interior) and so too small for most drive units with the motor behind the axle.

The steering rack is behind the axle line and right at the location where the motor would sit, but the Model S/X front drive unit places the motor very high to clear the front of the battery pack, so there's a good chance it would clear the rack - that won't work with a Model S/X rear drive unit (large or small).

I was ok with running in reverse. But doing so took up more engine bay space verses using a small rear drive unit. Which i still have to install and run in reverse lol.
Good point: if reversing the drive unit orientation, the "rear" drive unit would likely be more suitable. :)
 

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Discussion Starter · #6 ·
Okay so we might be in business with some added firewall clearance. I did some rough measurements. I orientated the drive unit at about 9° from level using a level and a protractor. I just used the coolant box on the top as my reference. Again these are rough measurements. I'm working with what I have quick access too at the moment. I the placed a square to the back of the housing not necessarily the mount because I can possibly make a mount that will fit better in the space. I measured from there to the center of the axle. Sorry for the picture quality but its a little over 260mm.
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Next I measured from the firewall of the car to were the current axle sits its roughly 220mm. I also measured from the passenger side frame rail to the steering column and its about 500mm so the motor would need to be pretty much shoved all the way towards the right side to clear and I will probably still need to notch out the frame rail a bit to get it over where it needs to be. As far as height is concerned the steering rack is pretty much level with the axles in the car so I will need to position the tesla drive unit slightly higher to clear it. I can lower the car a bit to offset the axle angle possibly if that becomes an issue.
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