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Porsche 911 (996) Tesla Swap

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Hello Folks,

Next week, I will begin pulling the engine out of a 1999 Porsche 911 C4 so that I can start an EV conversion project. I've done multiple engine swaps and have a good basic understanding of circuits. Plus, I've been watching a good amount of YouTube, including some of Rich Rebuilds Mini Cooper conversion series, so I got that going for me.

I would like to use the Tesla Model 3 Rear Drive unit from the standard range car (will be ditching the awd system). My understanding is that the Model 3s use a new motor type with more efficiency. I believe it is referred to as a Internal Permanent Magnet-Synchronous Reluctance Motor. Anyway, I figure, the Model 3 Standard Range does 0-60 in about 5 seconds and weighs about 700 pounds more than what this should weigh when it's done, so the standard range motor should be enough power.

Question for anyone who might know: Is the rear drive unit in the Model 3 Standard Range, the same as what comes in the Long Range/ Performance model?

Battery Range: I would be happy with 40kWh here, I figure that would give me about ~140 mile range, and not add too much weight.

I'm cheap. I hope to do the entire swap for around $10k (this takes into account getting some money back from selling Porsche parts). This means I probably will be looking for something other than Tesla battery modules.

I got to speak with Michael Bream at EV West today, he brought up a good point that the Model 3 motor places the axles behind the electric motor, thus transferring some weight forward in the car, whereas the Model S and Model X motors place the electric motor behind the rear axle (like a 911 engine sits). I figure I will be adding battery pack weight to the back of the car so the Model 3 motor would be okay.

I have heard that the Model 3 motor is newer for swaps and so people are still working on motor controllers and things like this. I'm all ears to any advice or information you think would be helpful.

YouTube video of the car I'll be swapping and some initial thoughts:
Ebay Listing for Model 3 Motor: 2020 Tesla Model 3 Rear Drive Electric Drivetrain Engine Motor Unit | eBay

Picture of the 911 being swapped.
Wheel Tire Car Vehicle Hood

Thanks for reading this. This is a dream project of mine and has taken a while to even get to this point.
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I would like to use the Tesla Model 3 Rear Drive unit from the standard range car (will be ditching the awd system). My understanding is that the Model 3s use a new motor type with more efficiency. I believe it is referred to as a Internal Permanent Magnet-Synchronous Reluctance Motor.
Yes, this is an internal permanent magnet (IPM) synchronous motor, and it is more efficient than an asynchronous (induction) motor. All IPM motors produce some of their torque from a reluctance effect; the Model 3 IPM motor certainly does, and is typical in this respect. This is only new to Tesla - the rest of the EV world has been using IPM motors for a decade.

Question for anyone who might know: Is the rear drive unit in the Model 3 Standard Range, the same as what comes in the Long Range/ Performance model?
I don't know, but since you're interested in the Model 3 rear motor you might want to watch Prof. John Kelly's Weber Auto video about this series of motors and drive units.

I got to speak with Michael Bream at EV West today, he brought up a good point that the Model 3 motor places the axles behind the electric motor, thus transferring some weight forward in the car, whereas the Model S and Model X motors place the electric motor behind the rear axle (like a 911 engine sits). I figure I will be adding battery pack weight to the back of the car so the Model 3 motor would be okay.
True, and I think the configuration with the motor ahead of the axle line is desirable, as long as it fits - the car was designed for only a relatively narrow transaxle ahead of the axle line. The 996 should be better for this fit than the older semi-trailing arm 911's.

I have heard that the Model 3 motor is newer for swaps and so people are still working on motor controllers and things like this. I'm all ears to any advice or information you think would be helpful.
The Model 3 is relatively new, so yes, it has only recently been used in swaps. Two of note, although they are not Porches and not even similar to a 911:
 

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Hi All, does anyone know if Tesla drive-shafts have a unique spline type? I'm wondering if there is any possibility a Porsche drive shaft may fit the Tesla drive unit?

I'm in the process of buying a Tesla small rear drive unit and wondering if I should get the Tesla axles too?
If a Porsche axle shaft would simply fit in a Tesla transaxle, why would companies such as Zero EV offer stub axles to fit the Tesla transaxle and connect to a Porsche axle shaft?

Porsche transaxles generally have output flanges to which the inboard CV joint of the axle shaft bolts; the available conversion stub axles have splines to fit the Tesla transaxle on one end and the VW/Porsche-style flange on the other end. The conversion stub axle provides the flange that the Tesla transaxle doesn't have; the Porsche axle shaft doesn't have a spline (to fit anything, Tesla or otherwise) on the inboard end.

To adapt the Porsche axle CV joints to the Tesla transaxle, you could buy Tesla axle shafts, use just the inboard end, and modify them to have a flange to which the CV joint bolts (which is what Yabert did for the similar situation in his VW van with a Chevrolet Bolt drive unit)... or you could just buy that part from Zero EV or someone else.
 

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Kevin said the bigger issue when wanting to pull power from any pack is that they need to be warm (but not too warm).
You will probably find tiger82's comments about battery temperature and performance interesting:
Pre-heating the pack certainly helps performance for the first session of the day...
More details about the car and its performance are in the builder's threads:
Tesla Powered Cobra Race Car
Modified Bolt Pack for Tesla Cobra EV Race Car
Model 3 Battery Pack for Tesla Cobra EV

I also really like the idea of air cooling them to keep it simple and light.
Direct air-cooling is simple and light, but not very effective. It may be good enough.
 
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