[WIP] 1977 Porsche 924 with 2019 Leaf Stack

[kangasp]

Hi all,

I'm working on a swap that will put a 2019 leaf stack in a 1977 Porsche 924.

This will be a slow build. I'm doing it with 3 other friends (we're in Oregon) and we treat it like a book club. We get together once a month and get a little more done. We don't need it done quickly and it's just a fun way to hang out.

So far we bought a leaf with front end damage. We've pulled the motor out and did our first spin using the battery it came with (not the original), and the zombieverter. It was just a short spin on the bench as proof of concept, to convince ourselves we could wire and configure it correctly.

We bought a 924 and removed all the ICE components. Now we're looking at options to mount the motor in the back. The plan is to use the leaf diff, and to cut and weld the half shafts together (pretty common, I think). Then test the fit up and then have real ones made in a shop. I'd love to get a limited slip diff, and I know they're out there. But will wait to see how this does first.

I think we're going to take the stack apart, and mount the inverter and PDM separately. If anyone has strong opinions on whether or not that is creating a headache for us, I'd love to hear your thoughts. We might also remove the backseats to make more room and give us more options. The backseats aren't really usable anyways.

There's a YouTube channel of our progress here:
https://www.youtube.com/@CurrentEndeavorsCrew/videos

I'll update as I can. Here's a few pics of the items in question.

[ianlighting]

I think we're going to take the stack apart, and mount the inverter and PDM separately. If anyone has strong opinions on whether or not that is creating a headache for us, I'd love to hear your thoughts.

Splitting the stack has been done many times, so it’s an option if you need it. Benjamin Nelson did a good Leaf stack tear down on YT if you need pointers. On my build I ran the coolant backwards through the PDM due to how it was arranged and has worked fine (1000+ miles). I used Johannes’ PDM tear down vid to help me decide that was likely to work. There’s also some useful 3D printable covers around depending what HV you expose in your new arrangement.

[johu]

This project also uses a split Leaf stack

[Bratitude]

Alternativly sell the pdm, and get an outlander obc off ebay for cheap.

Much smaller, easier to mount and a lot less weight.

Yes only 3.3kw but if you set up CHAdeMO you’ll be fine for “road trips”

Pdm’s are worth a lot being the fast charge contactors and other parts fail in them, makingthing wortg $$$ for repairs.

Note on cv shafts… I have one set left of drive shaft adapters…. Which will allow the stock Porsche 100mm cv joints to mate to the leaf gearbox…. Shameless plug but though I’d mention it

[kangasp]

Thanks for the comments!

That was a great video. I feel so bad for him frying his inverter and PDM by switching the polarity. I keep holding my breath and trying to go slowly to not fry our inverter.

It looks like he went the route of installing the motor to run in reverse by switching two of the phases going into the motor (I've seen the resolve EV docs on this). So, this must be safe for the gearbox? The oil still gets splashed around as it's supposed to and long term wear is the same as forward? I'd be grateful for any pointers of where to look or personal experience / miles put on this kind of install. It would be easier for our install to be in reverse, but I've been pretty hesitant cause I don't know enough about it.

Thanks Bratitude for the tip on the outlander OBC. I'll look into that. The size reduction looks nice. If we figure out a way to easily fit the full leaf stack I think we'll go that way, just because we have it, and it's a known solution.

Also, thanks for the heads up on the drive shaft adapters. They might be a good solution for us. I know the length of those shafts is important, and because we're switching the Porsche diff with the leaf diff it probably throws it off a little. More options to explore. I didn't see it in your shop. Is it this: https://bratindustries.net/product/leaf-to-vw-adapter/ ? Anyways, I'm interested in dimensions if you have a link.

[ianlighting]

Oil -
The search bar on this site works pretty well so it’s worth trying. But I had remembered there was a previous discussion on Cera’s page because I’m following her VW build. So this might be useful… https://openinverter.org/forum/viewtopi ... 681#p40681

Or try contacting Isak at Resolve because his 924 was done a few years ago now.

[kangasp]

Wow, what a great build thread. Thanks for the link. I tried searching before, but must have missed some terms or something.
Now I think we might open up the leaf gear box and see what kind of bearings we have.

[DVD3500]

Nice!
I seriously thought of doing a 924 .... I had one back in the 90s....
Loved it!