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If i buy a complete Nissan Leaf, will i have all the parts to do a conversion to my BMW? Offourse i will have a motor, charger, battery, electronics etc. everything.
I can do fabrication myself.
 

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If i buy a complete Nissan Leaf, will i have all the parts to do a conversion to my BMW? Offourse i will have a motor, charger, battery, electronics etc. everything.
I can do fabrication myself.
You would have everything electrical and electronic, except for whatever you need to do to interface the Leaf bits with the remaining BMW bits.

You would still need the mechanical parts to adapt whatever part of the Leaf drive unit you use to whatever part of the BMW driveline that you keep, plus the housings for the battery packs you build (and fill with Leaf modules and other components), and the structural parts to mount everything. That might be all stuff you can build, or mostly stuff you would need to buy, depending on your design and fabrication abilities and facilities, and the design you choose.

Can you describe your plan for using the Leaf components, and which BMW they are going into? For instance, where will the motor go, and what will be used for a transmission and differential?
 

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Just looking at different options right now. But there seems to be a lot of options.
Ideally i would like to keep it all BMW so use an i3 motor etc. But there is not so much info on this motor and electronics, except for Damien from EVBMW offcourse, but thats all i could find.

In my opinion it is best to buy a complete car and use as much of it as possible and sell of the remaining bits to get some money back.
So i could use tesla parts, they are used a lot and don't seem to have any secrets anymore. But a salvage tesla still costs quite a few bucks.
So i was looking at Leafs, they are a lot cheaper, they don't seems to have any secrets anymore, everything from motors to electronics can be reused and since there are a lot of them selling off the est of the parts shouldn't be to hard. Only thing is i might have to buy extra batteries because of the small range a Leaf has.

It's all going in an E30 Touring, i spend the last year making sure the E30 is rust free, all suspension is redone, all bushings are replaced by new ones. It's ready for another 200.000miles.
I don't know yet where i want to mount everything. Keep the transmission and bolt a motor to that. Keep the rear differential and bolt a motor to the diff or do it like the Tesla powered BMW, create a new sort of subframe/bracket setup and mount the motor in place of the diff and thus loosing gearbox and diff.

Lots of possibilities. Lots of decisions to be made.
 

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Just looking at different options right now. But there seems to be a lot of options.
...
Lots of possibilities. Lots of decisions to be made.
There certainly are: although lots of them just don't make sense, there are still multiple viable options. And each decision affects the other options.

Ideally i would like to keep it all BMW so use an i3 motor etc.
The idea of a consistent manufacturer is nice, but of no practical value unless the parts work together... and that's unlikely between an E30 and an i3.

... So i was looking at Leafs, they are a lot cheaper, they don't seems to have any secrets anymore, everything from motors to electronics can be reused and since there are a lot of them selling off the est of the parts shouldn't be to hard. Only thing is i might have to buy extra batteries because of the small range a Leaf has.
Adding to an EV pack is problematic. If you add modules in series, you will have a higher working voltage which is unlikely to work well with the charger, BMS, and inverter/controller that came from the donor EV. If you add in parallel, you have to completely double the battery to have the same voltage, which is a huge pile of modules... and still likely problems with the stock supporting components from the donor EV.

It's all going in an E30 Touring, i spend the last year making sure the E30 is rust free, all suspension is redone, all bushings are replaced by new ones. It's ready for another 200.000miles.
I don't know yet where i want to mount everything. Keep the transmission and bolt a motor to that. Keep the rear differential and bolt a motor to the diff or do it like the Tesla powered BMW, create a new sort of subframe/bracket setup and mount the motor in place of the diff and thus loosing gearbox and diff.
All valid options, but if you try to put a Leaf drive unit at the rear axle you have the problem that the E30 suspension arms are ahead of the axle line and so is the motor (unlike the Tesla Model S/X unit which has the motor behind the axle), so they will not fit together. You can flip the drive unit around, if you can sort out any gear lubrication and motor control issues with operating it most of the time in reverse.
 

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If i buy a complete Nissan Leaf, will i have all the parts to do a conversion to my BMW? Offourse i will have a motor, charger, battery, electronics etc. everything.
I can do fabrication myself.

You will have what you need to make the BMW as OEM as a Leaf. However The Leaf is a little fussy about some things. Seat sensors, door sensors. Air bag. Not sure how that stuff will interface. But you will have fast charging. That is a deal breaker for any conversion. Without fast charging you have a local ev.
 

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It's theoretically possible to take a complete Leaf and transplant the system into another car and have it drive as if it was a Leaf (with lots of errors due to missing bits). It's not guaranteed though...Specifically, people claim to have done it, but nobody has stuck around to talk about it or detail it in the last year (that I've seen). My attempt is documented here:

https://www.diyelectriccar.com/forums/showthread.php?t=199847

It's all or nothing, and that includes the gauge cluster, shifter, various computers matched to the ignition key code...If you lose a necessary computer or sensor, the Leaf VCU will prevent the system from doing anything useful. If you can't get the whole thing working, you'll need to buy an aftermarket controller, charger, BMS, DC-DC, etc. Costs another few grand.

If you can hack the CAN and rig up an arduino with code or some such, you might be able to control the Leaf DC-DC, charger, BMS, and HVAC...saving thousands and becoming a hero to the community in the process. People have figured this stuff out, but they're keeping the information as a trade secret to sell products. There is as-of-yet no open source hardware or software that works out of the box without significant effort, though there are some fragments out there.

I believe that buying a whole Leaf is still the cheapest way into a battery and motor that is highway-capable, so it might still be the way to go. You'll get fuses, contactors, wiring, and other components that maybe someone will crack open while you put your build together...
 

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If the motor can fit in the rear without massive modification, that would be the best route in terms of space/weight/simplicity, and also get rid of the weak links in the existing drivetrain. I suspect it's...involved.

Second best option that I see is to mate the Leaf motor to the transmission and limit the torque (or hope it holds). That would give you tire-smoking power and a high top speed at the cost of a few hundred pounds, battery space, and the complexity, maintenance, and fluids needed for the transmission and diff. They made AWD E30s at some point (or was it just the 5?) that might be compelling addition for a wagon with more torque than an M3...
 

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If the motor can fit in the rear without massive modification, that would be the best route in terms of space/weight/simplicity, and also get rid of the weak links in the existing drivetrain. I suspect it's...involved.
The E30 - like other BMWs of the era - had a semi-trailing arm rear suspension. That means interference between the suspension arms and a transverse drive unit with the motor ahead of the axle line, such as the one from a Leaf. As I noted earlier, that leads to two options:
  1. complete replacement of the suspension, or
  2. running the Leaf drive unit in reverse.
Lance's Electric Clan Crusader has semi-trailing arms, and runs the Leaf unit in reverse.

Of course, even with the suspension issue handled, there isn't enough room for a complete drive unit without body modifications. It certainly is "involved".

They made AWD E30s at some point (or was it just the 5?) that might be compelling addition for a wagon with more torque than an M3...
There was apparently an E30 generation AWD 3-series - the 325iX starting in 1985. I still don't see the logic of using a complex and bulky AWD system designed to get the output of one engine to all four wheels with an electric motor. There are reasons that every production AWD EV has separate front and rear motors.
 
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