Porsche Boxster with Tesla Drivetrain

[Kevin Sharpe]

Zero EV (here) have announced a Porsche Boxster build that they will document as a four part mini series on their YouTube channel (here).

The build will use their commercial version of the open source inverter controller developed by Damien and Johannes. They will also use the Tesla 11kW Charger, Tesla DCDC, and a 36kWh Tesla battery from the Smart

They have also announced that a bolt in kit for the 911, 930/964, and 993 is in development.

[tom91]

First episode is out.

[tom91]

Project coming along nicely. All the bits out last episode now new bits going in.

Battery box, a Mercedes B class pack stacked in 6 above 6, giving 36kWh and a rear small Tesla motor get installed.
Also fitted a vacuum pump and charging socket.



Currently chasing down the wiring, luckily there is already an Electronic pedal in there to reuse.
The gauges will be kept and driven from a Teensy to make them work to display power instead of RPM and SOC instead of fuel level.

[tom91]

Quite some more work done on the car. She is back on her wheels ready to be 12V wired up.

[johu]

Very clean work, thumbs up
Do you think it would be worthwhile bypassing the radiator when in battery heating mode?

[tom91]

Very clean work, thumbs up
Do you think it would be worthwhile bypassing the radiator when in battery heating mode?

Yes once we work out how the Tesla three way valve works we will do it, might just plumb it in and leave it un used like a few other features on the car.

[MattsAwesomeStuff]

Do you think it would be worthwhile bypassing the radiator when in battery heating mode?

Yes once we work out how the Tesla three way valve works we will do it, might just plumb it in and leave it un used like a few other features on the car.

You could just use two SPST valves instead of a SPDT valve, if the SPDT from Tesla is weird. One normally flowing, the other normally blocked, and then power to each toggles them in the opposite position and sends coolant to the opposite branch of the Y. (I don't know valve terminology, hopefully that makes sense).

[jon volk]

Info on the Tesla valve wiring/function here
https://www.diyelectriccar.com/forums/s ... 70p12.html

[tom91]

Sorry gents, meant to say once we get the software written for our thermal controller.

As we have a full bridge so can drive the valve into the required positions. Plus we got a bunch of tesla valves laying around so we might as well use them. Will post when I got some testing done.

[Boxster EV]

I have to say, it's very impressive how quickly and comprehensively you've gone about this project.

Thanks for sharing.

[tom91]

Sorry gents, meant to say once we get the software written for our thermal controller.

As we have a full bridge so can drive the valve into the required positions. Plus we got a bunch of tesla valves laying around so we might as well use them. Will post when I got some testing done.

So I got the valves working, using a half bridge just being turned on and off, this does not allow mixing of the circuits. Most applications this is fine.

The feedback is a DC voltage ranging from 1-10V depending on valve position.

[tom91]

Currently working on getting the gauges working.

Turns out the 2001-2004 models, like the one in this project, use canbus to transmit most information from the engine ECU to the dash.

If anyone has any can bus information on the Porsche Boxster 986 or the 996 it would be very helpful.

Currently all lights are off except the coolant temp warning and coolant gauge is pinned. Plan is to hook the engine back up, all be it outside the car on a pallet and then see if the lights go off.

One big issue that has been identified is that the Porsche Boxster 986 and 996 have an unusal way of controlling the fuel level gauge;
1. Full to 1/4 tank is off fuel sender
2. 1/4 to empty is done by fuel consumption using the engine ECU

[Jack Bauer]

A good source for CAN info I have found are engine swap forums.

[tom91]

A good source for CAN info I have found are engine swap forums.

Correct, I have most of it sussed out now. Will be testing it Monday.

[tom91]

So we have the gauges working, only the fuel level gauge and stupid error light on the coolant to fix.

Attached is the .dbc file that is used.

[tom91]

Not a lot has happend, waiting on the shafts and it is prepared for all the wiring.

I have also uploaded the dxf to make a Boxster fuel filler to type 2 inlet adaptor in case anyone wants to convert a Boxster.

[Boxster EV]

Thanks for these files, Tom. Much appreciated.

[tom91]

[Boxster EV]

Love the way you left a bottle of oil in the frunk.

[tom91]

Love the way you left a bottle of oil in the frunk.

I just noticed that too, we did learn though the porsche coolant system is a pain to bleed.

Got most of the wiring figured out to reuse alot of the OEM relays and other components. Loads of testing to do once we can get back to driving off site.

[Boxster EV]

Yes, I have used most of the original relays for brake booster and power steering etc. I have also used an OEM tiptronic shifter with micro switches positioned to enable F/R.

Simp BMS screen mounted on centre console where CD slots were. Warning lights on dash off.

I’m still to fit a cooling system so I’ll bear your feedback in mind.

Your conversion looks really good. What is Chris planning to do with the car?

[tom91]

This is a development vehicle for the tesla SDU.

Plus good car to take clients out in.

[Speedy]

Fabulous work guys and nicely YouTubed, enjoying the videos.

I'm wondering what the process is for working out all the CANBUS messages, can someone point me to a video or page with info on this, please.

[tom91]

Fabulous work guys and nicely YouTubed, enjoying the videos.

I'm wondering what the process is for working out all the CANBUS messages, can someone point me to a video or page with info on this, please.

Google, google and then some more google. If that does not work you need to start can captures and changing one thing at a time and hunt for the values that change.

The Boxster is now out and driving around, she will easily do 80 miles on a charge. Keep in mind this is an abused pack that is quite out of balance and the car is not being driven conservatively.

To celebrate we got a new project in the shop a Gen 2 Mazda MX5.

[Evtorque]

great info I have shared these videos in our open workshop classes.

Cheers Conrad