Tesla LDU Inverter Removal and Relocation

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ImportFanatiK
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Tesla LDU Inverter Removal and Relocation

Post by ImportFanatiK »

Background:
Hi all, I am in the early stages of trying to convert a Mazda RX8 to use the Telsa LDU.
I have managed to get the LDU running on open inverter and am now staring long and hard at the rear subframe and strategizing how to squeeze the LDU into such a small space.
IMG_0307.jpg
Unfortunately the LDU is about 1" too long, and it will interfere with the upper control arm mounts on the rear subframe.
My conclusion is that the path of least resistance is to shorten the LDU by removing and relocating the inverter.
This will mean the center point of the LDU differential will be offset from the RX-8's center by about an inch or two, which could cause some degree of torque steer,. but I think it should be small, and is ultimately the lesser of evils.

Questions: I will try to summarize the answers below for future reference by others as I learn more about this topic:
Tesla LDU Inverter Relocation Options: Telsa LDU Inverter Removal Instructions:
ImportFanatiK
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Re: Tesla LDU Inverter Removal and Relocation

Post by ImportFanatiK »

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Boxster EV
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Re: Tesla LDU Inverter Removal and Relocation

Post by Boxster EV »

It will be a pain to relocate the inverter as you’ll have to overcome all of the cooling passageways AND the wiring to each phase. Anything is doable but not worth it IMO. Why don’t you use a SDU? or, an M3 motor.
Porsche 986 powered by a Tesla large drive unit. Backwards. Build documented here and Instagram @tesla_porsche here.
P.S.Mangelsdorf
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Re: Tesla LDU Inverter Removal and Relocation

Post by P.S.Mangelsdorf »

Are there any alternate orientations you could mount the drive unit to avoid those suspension mounting points? Backwards, upside down, tilted? Doing so would require modifications to the oil pump but that is far less intensive work and a far more well traveled path.
If at first you don't succeed, buy a bigger hammer.

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ImportFanatiK
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Re: Tesla LDU Inverter Removal and Relocation

Post by ImportFanatiK »

P.S.Mangelsdorf wrote: Tue Jul 02, 2024 3:03 pm Are there any alternate orientations you could mount the drive unit to avoid those suspension mounting points? Backwards, upside down, tilted? Doing so would require modifications to the oil pump but that is far less intensive work and a far more well traveled path.
That's probably a wise suggestion.
My original plan was actually do use a leaf motor and use the resolve setup. But as fate would have it an LDU fell into my lap, and I am determined to use it.

I have been staring at the problem for months (see thread here: viewtopic.php?p=72368#p72368 )and have come to the conclusion that this is by far the path of least resistance in terms of RX8 + Tesla LDU, and I'm not willing to consider a different motor or car as I already have the car on jack stands in the garage, and I already have the LDU running on open inverter. So I feel pretty committed to this combo at this point.


The inverter came out pretty easily though tonight actually. That video showed everything.
But there was actually 3 wires I had to disconnect and not just one.
ldu inverter 1.jpg
ldu inverter 2.jpg
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Re: Tesla LDU Inverter Removal and Relocation

Post by ImportFanatiK »

One other interesting thing I noticed immediately after removing it.

I cant set it down! (Well not easily).
Since its designed to be bolted via the coolant plate, there are no safe flat surfaces to set it down.
So first order of business is going to be to 3d print an inverter stand that will let me store it safely somewhere with the cover attached.
I will post the file and pictures in case anyone else wants to make their own.

From there, I have decided I am going to try 3d print my own coolant adapters, and then make them on my milling machine.
(I bought it years ago planning to convert it to a CNC but never converted it or even used it at all actually, so I will have to do some learning on that front first I suppose).
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Re: Tesla LDU Inverter Removal and Relocation

Post by muehlpower »

With a reasonable amount of effort, I think you could make a cooling water distributor from an old housing of a broken LDU.
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Re: Tesla LDU Inverter Removal and Relocation

Post by P.S.Mangelsdorf »

muehlpower wrote: Thu Jul 04, 2024 8:16 am old housing of a broken LDU.
I've seen some pop up on Ebay from time to time.

Oh and you've got a Sport LDU, Nice!
If at first you don't succeed, buy a bigger hammer.

1940 Chevrolet w/ Tesla LDU - "Shocking Chevy" - Completed Hot Rod Drag Week 2023 and 2024

https://www.youtube.com/@MangelsdorfSpeed
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