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Tesla Powered BMW E31 8 Series

40531 Views 110 Replies 25 Participants Last post by  jackbauer
So some of you might already know about my E31 conversion as it's been going on 3 years now! Currently running a Siemens 1pv5135 motor and DIY inverter and 6 speed manual gearbox. Has been running very well the last few months but with the Tesla components becoming available and my work on the open source control boards progressing nicely I've decided to convert the E31. Again.

I had originally thought to use the small high efficiency drive unit but decided to go all in and put in the Large rear unit for 450hp+ :D

Going to be getting some help and the use of a workshop and vehicle lift for the drive unit install as it will need some serious work done to the rear subframe and boot floor. Once the drive unit is in then I can start putting some batteries into that nice big empty engine compartment. Should make quite a fun car and test bed for the open source control board. Stay tuned:)

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That is so neat!
You could fit that to almost anything
It is tidy, but the fit is only easy into rear-wheel drive vehicle with a trailing or semi-trailing arm rear suspension; the motor will interfere with the control arms or subframe of almost any multi-link or double-A-arm suspension not designed specifically to accommodate this drive unit. That design is obsolete now, but was standard practice for rear-engined vehicles (especially VW) and for a few decades of rear-drive front-engine cars with IRS... such as BMW, Mercedes, Datsun, Toyota, etc.

It seems inevitable that someone will do a Datsun 510 - because everything get tried with a 510 by someone - but good 510 bodies are rare (they are all over four decades old now) and they are in demand for use with the original drivetrain configuration.
 

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It is tidy, but the fit is only easy into rear-wheel drive vehicle with a trailing or semi-trailing arm rear suspension; the motor will interfere with the control arms or subframe of almost any multi-link or double-A-arm suspension not designed specifically to accommodate this drive unit. That design is obsolete now, but was standard practice for rear-engined vehicles (especially VW) and for a few decades of rear-drive front-engine cars with IRS... such as BMW, Mercedes, Datsun, Toyota, etc.
Disagree completely
The advantage of that design is that you only need mounting points for the cross beam
It would be a doddle fitting that in the back of almost any front or rear wheel drive car

All you need is lots of cutting discs and the correct attitude
 

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That looks really nice. It also looks a lot like the back end of my Supra. Too bad my wife would be really angry if I went out and bought a Tesla drive unit and all the inverter bits after having spent so much on the wrecked Leaf. Guess I have to keep on the road I've laid out for myself.

B
 

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...
The advantage of that design is that you only need mounting points for the cross beam
It would be a doddle fitting that in the back of almost any front or rear wheel drive car

All you need is lots of cutting discs and the correct attitude
If all you need to cut out is some crossmember that's not bad (although more work than with semi-trailing arm setups like this older BMW), but when the cutting disks take off control arm mounts it's not quite a "doddle". ;)

In a Model S the motor sits between suspension mounting points, but remember that this is a wide car; those points are closer together in a smaller car.

I don't think Kevin or others have found putting a Tesla drive unit in to VW van to be trivial, either; they're getting there, but had to cut vehicle structure to get it in... and that's one of the easy semi-trailing arm designs (although they're converting to an aftermarket double-A-arm design as well).
 

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I'm putting a tesla drive unit in the back of a 1969 Jaguar XJ6. Im aware it will be complicated to fit and i need to add an upper control arm.
I think there are plenty of people facing this problem so soon enough solutions will abound, for now, a bit of positivity and can do attitude will have to do.

If i can get a good system for this, i think anyone can.
 

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I don't think Kevin or others have found putting a Tesla drive unit in to VW van to be trivial, either; they're getting there, but had to cut vehicle structure to get it in...
On the prototype VW Bus we cut one chassis cross member. However, we have realised that this is unnecessary and the next version will bolt on without any cuts.

The VW Beetle requires no cuts and as a non-car person I'd say it's trivial to fit a Tesla drivetrain... indeed, it was much easier than removing the old ICE components :)
 

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the motor will interfere with the control arms or subframe of almost any multi-link or double-A-arm suspension not designed specifically to accommodate this drive unit.
Do you know the width of the motor? Did you measure prior to installation?

I am wondering if it might fit in the back of a Porsche 996 widebody. There is a lot of room between the subframes, and LOTS of room behind them. Even if it had to be mounted a little way back, and a little more angle on the CV joints.
 

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I am wondering if it might fit in the back of a Porsche 996 widebody. There is a lot of room between the subframes, and LOTS of room behind them. Even if it had to be mounted a little way back, and a little more angle on the CV joints.
The more recent rear-engine Porsches (since the 993, the first without semi-trailing arms) might be an unusually easy fit for a Tesla drive unit, among cars with multi-link rear suspensions, because they are already designed to clear a wide engine immediately behind the final drive housing. :) Obviously, there's no crossmember right behind the axle line, but clearing the rear control arm inboard mounting points and their aluminum subframe is likely still a challenge.
 

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Do you know the width of the motor?
There's a 3D scan of the 'large' drive unit on GrabCAD (here).

If you need more information then try asking Chris Hazell (here) who's using the 'large' drive unit in his 350Z project (here). You may find Damien's a little busy ;)
 
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