All modern EVs use a motor integrated with a transaxle; the Tesla and Leaf configurations are very similar, following the most common pattern of one motor per axle, a two-stage single-ratio reduction gear set, and an open differential, all mounted transversely. The biggest differences:The 'Nissan Leaf' motor/Inverter: I think it has a good cost and more than enough power for what I need and many options of controler board in the market (I was considering buying one from open inverter here in Germany). I was considering a small unit from Tesla but as it comes integrated to the diff, I would need to cut the spare wheel well to assembly it under the rear floor and I don't know how the TÜV here would see that. If I can make it work work simpler with the leaf, why not?
- All Model S/X drive units and the Model 3 front drive unit place the motor behind the axle line, while the Leaf and Model 3 rear drive units place the motor ahead of the axle line.
- The Leaf motor does not share lubricant or coolant with the transaxle and is readily separated from the transaxle; in contrast, the Tesla (at least Model S/X) motor's end housing also one side housing of the gearbox, and the same oil is pumped through the motor bearings and the gearbox.
- Tesla inverter housings are attached to the transaxle housing, opposite the motor, while the Leaf inverter is stacked on top of the motor.
Gearing is certainly an issue. Are you sure that the converted E30 would be significantly lighter, even after adding a useful amount of battery?NO Gearbox: Here is my biggest doubt. I would like to go without tranmission. I would like to link the motor to the diff just modifing the existing shaft. If possible at the fuel tank area, if not at the original transmition spot. The diff would be a 4.4 ratio from the e30 316 AT. The problem is that is much longer than the 8 ratio from the leaf. The e30 is lighter than the leaf and has smaller wheels but would that be enough to make it work? (work for me means: don't destroy itself and 0-100 around 10s).
One solution to this is to add a reduction gearbox on the output of the motor (less than 2:1 ratio is all that is needed), but that's neither trivial nor cheap.
I think a realistic look at the size of the motor versus the available space in either the transmission tunnel or the fuel tank area is called for. The tunnel is unlikely to be as wide as the motor diameter and the fuel tank is nowhere near as tall as the motor diameter.