[DRIVING] Porsche Boxster 986 Tesla conversion [FINISHED]

[joromy]

A few pictures and meandering thoughts following my recent Tesla gen 2 charger installation with V5 logic board.

I have the same orientation of the charger, and I have trouble with overheating of the top module.
I'm wondering if it's possible to make some air bleed or vent in the top, to get coolant flow?

[Boxster EV]

A few pictures and meandering thoughts following my recent Tesla gen 2 charger installation with V5 logic board.

I have the same orientation of the charger, and I have trouble with overheating of the top module.
I'm wondering if it's possible to make some air bleed or vent in the top, to get coolant flow?

I’m not having this issue, in fact the charger only feels a little warm to the touch.

Could be due to a few reasons:

- I’m running a fairly large radiator AND I suspect the LDU is an efficient cooler. I was also super fastidious on bleeding the system and did so with the charger in a horizontal position before moving it into the final vertical position.

-I’m not running the charger at full capacity due to my 32amp EVSE limitations.

[canadasconvert]

As per my post above, the below image shows the mounting of the Hella UP28 vacuum pump (2009 Vauxhall Astra) in the Boxster mid-engine-bay. The system incorporates a Dracarys vacuum pressure switch and non return valve - everything purchased off eBay. The vacuum switch effectively provides a ground to the relay once the system has reached pressure and shuts off the pump. I used one of the existing defunct relays from the ICE relay box and wired it all in to look as OEM as possible (the wiring isn't yet finished). I managed to re-purpose most of the existing vacuum lines and just purchased a little extra to incorporate the new hardware. Total cost of everything was about £50

 

Everything works as expected. The only modification I think I'll need to make is to provide a vacuum reservoir to the system, as presently the relay can flick on and off a little too quickly with the slightest of pressure change and I think this would be improved with more volume in the system.

 20190901_175713_zpsfthnugrp.JPG

The power steering pump is a TRW unit from a Vauxhall Zafira. The mountings I've used are a little Heath Robinson however I've managed to use existing hardware and mounting holes. I've also managed (just about) to use the existing high pressure line without any modification whatsoever! The low pressure side required extra tubing. The pump spools up really well and seems to work fine - again I used an existing relay, 50 amp fuse and have wired everything to look OEM.

20190901_175744_zpsnfxlfini.JPG

Here's a picture of what the car looks like underneath with just the coolant, PS, brake and A/C lines in place. I'm intending in using the existing fuel line clips to mount the high voltage cables which'll run to the cars front batteries and type 2 charge port.



Finally, the car is due have the drive unit mounted at a local race-car welding specialist at the end of this month. The chap doing it seems very competent and open minded so I'll post his details up if everything goes well.

 

Thoughts so far = EV conversions take more decision making, time and money than I originally thought. And, it's a very long road. 

Well yes Dracarys switch can act up. But really it is just a mechanical switch with brass body, membrane, nut and spring. You torque the internal nut and increase pressure so equilibrium is reached sooner or later.
Whenever it acts up i remove it from my car and clean it up and reset the spring. This spring sometimes wedges against membrane and switch is allways on or wont work. After i cleaned it, it works as before.

I just don't want to have to worry about 'servicing' it every few months. Better to just buy the unit above and be done with it. Also, the multicomp version is adjustable. I've done 250 miles on the car since fitting and very pleased with the braking performance.

I'm just embarking on doing a similar Tesla conversion. Currently the motor, tranny and gas tank are out. I have the Tesla LDU, Kia soul batteries, charger BMS and other misc. pieces. Mechanically I should be fine, but I will struggle electrically.
I am going to have lots of questions. Stay tuned
First question is what location in the fuse/electrical box did you use to power your vacuum pump and PS pump?

[johu]

Hi and welcome just a quick note: please quote a bit more precisely

[arber333]

Well yes Dracarys switch can act up. But really it is just a mechanical switch with brass body, membrane, nut and spring. You torque the internal nut and increase pressure so equilibrium is reached sooner or later.
Whenever it acts up i remove it from my car and clean it up and reset the spring. This spring sometimes wedges against membrane and switch is allways on or wont work. After i cleaned it, it works as before.

I'm just embarking on doing a similar Tesla conversion. Currently the motor, tranny and gas tank are out. I have the Tesla LDU, Kia soul batteries, charger BMS and other misc. pieces. Mechanically I should be fine, but I will struggle electrically.
I am going to have lots of questions. Stay tuned
First question is what location in the fuse/electrical box did you use to power your vacuum pump and PS pump?

Hi

Let me update this info. I absolutely hate the mentioned switch. For a time it seemed it would only require little maintenance (WD40 spray) with copper shimm as seal and it would work nicely for 3 months. But lately it started to act up. I think membrane would stick and switch wouldnt conduct. Then servo would dry up and brakes would be heavy... I could still brake effectively, but with a heavy foot...
It now requires for me to strike it in the morning (with no13 spanner ) and it would work through the day...

I ordered the volvo vacuum switch and i will test it when it arrives. Maybe it will fare better?

Location for vacuum pump should be somewhere you can easily have access to in case you need to reattach hoses or exchange the pump.
You want to use some lenght of hose so it acts as a buffer for your vacuum. Also dont forget to put non-return valve before the switch!

Hydraulic pump you need to put somewhere where you will be able to fill up with oil if required. Also be advised you need to seal the pump from the chassis as that noise is unbearable. Use original mount if possible and adapt/weld it to where you want it.

I put all my relais inside one contact box near the original relay/fuse box. See here: https://leafdriveblog.wordpress.com/201 ... ntact-box/
I put one 80A fuse on the side to supply the current to everything including HPAS pump. From there i pulled various small fuses and relays and wired sensors.
When i was absolutely sure what all the engine wires are for i cut them near the connectors and spliced/extended them with numbered wires. those i pulled inside the contact box. This way i have access to all sensors in the car and if i find out i forgot to implement something those wires will still be there and i woulod know what no. they are on. So dont cut anything untill you are absolutely sure you can simulate engine running!

[Boxster EV]

I'm just embarking on doing a similar Tesla conversion. Currently the motor, tranny and gas tank are out. I have the Tesla LDU, Kia soul batteries, charger BMS and other misc. pieces. Mechanically I should be fine, but I will struggle electrically.
I am going to have lots of questions. Stay tuned
First question is what location in the fuse/electrical box did you use to power your vacuum pump and PS pump?

Just to respond your specific questions: For the brake booster I repurposed a defunct relay from the relay 2 support panel which is in the boot/trunk. You could use 2, 5, 8 or 10.

As per Arber DO NOT use the Dracarys switch as it's junk. Instead use the replacement one I referenced in this thread. I placed the switch in the frunk near the main cylinder here:

[canadasconvert]

Nice work. I have the same vacuum and power steering pump units.
Are you saying the brake booster doesn't have enough volume itself to prevent the vacuum pump switching on and off excessively?
Or do you mean as soon as you touch the brakes and the booster vacuum drops a bit the electric pump comes on immediately?

I'm in Canada and doing the same conversion. (Except my steering wheel is on the proper side) LOL
For the power steering motor/pump, I have been looking at ones that came out of a Volvo S40. These are easier to get here in North America. Does anyone know if this would be a good fit?

[arber333]

Nice work. I have the same vacuum and power steering pump units.
Are you saying the brake booster doesn't have enough volume itself to prevent the vacuum pump switching on and off excessively?
Or do you mean as soon as you touch the brakes and the booster vacuum drops a bit the electric pump comes on immediately?

I'm in Canada and doing the same conversion. (Except my steering wheel is on the proper side) LOL
For the power steering motor/pump, I have been looking at ones that came out of a Volvo S40. These are easier to get here in North America. Does anyone know if this would be a good fit?

Here you go, pump from S50. Run in backup mode without CAN. If you can run it with RPM and speed feedback please post your results here.
https://www.diyelectriccar.com/threads/ ... 828/page-5
I am not sure if others are the same...

[arber333]

Some more update on the vacuum switch...

Since i sprayed the insides of the switch with welding nozzle spray (anti spatter) i got much less freezes of my Vacuum pump. It really seems like a contact would weld itself to the membrane with use. I dont have this happening with Mazda MX3 though i use the same kind of switch.

[arber333]

Some more update on the vacuum switch...

I replaced my vacuum switch with Volvo XC90 switch. See here...
viewtopic.php?f=9&t=335&p=19239#p19239

[canadasconvert]

Thanks for the info on the vacuum pump.

[canadasconvert]

I'm just getting the components for the main contactor box together. So far I have the fuse, two - 700Amp main contactors, one 50Amp contactor, the and the two resistors.

A few simple questions:
1 - what was the size of your original Contactor box?
2 - where did you find a one with a clear lid?
3 - what is the black item between the two main contactors?
4 - What are the white fuses for in the box?
5 - what is the black/grey appendage just outside the fuses?
6 - do you have a manual disconnect for the contactor box?

[Boxster EV]

I'm just getting the components for the main contactor box together. So far I have the fuse, two - 700Amp main contactors, one 50Amp contactor, the and the two resistors.

A few simple questions:
1 - what was the size of your original Contactor box?
2 - where did you find a one with a clear lid?
3 - what is the black item between the two main contactors?
4 - What are the white fuses for in the box?
5 - what is the black/grey appendage just outside the fuses?
6 - do you have a manual disconnect for the contactor box?

Are you doing a Boxster 986 conversion? If so, don’t use such a big HVJB - where are you putting the box? The black contactor was intended to be for my charger but I never used it. I have another contactor in the front that breaks the pack in half in emergency.

The white fuses are for the charger and the dc2dc. I have upgraded them since with HV DC fuses.

You 110% need a HV disconnect. Get the gigavac version from EVWest.

I’ve got loads of pictures to update this thread. Will try and do that in the coming week. Alternatively you can see most of them on my Instagram.

[rjmcdermott81]

Hey - this build thread is a great guide. It looks like you modified a stock auto-shifter to trigger R-N-D. Any details that you can share on how you did that?

[canadasconvert]

Thanks for the reply on the Contactor Box.
Yes - I am converting an '02 Boxster S (986) that I got for a song.
I want to put the contactor box where you have it over the Tesla motor and beside the battery.

[canadasconvert]

Another questions regarding the accelerator.
Did your Boxster 986 have cable or an electronic gas pedal?
The '02 Boxster S has an electronic pedal so hopefully I can tie this directly into the Tesla Open Inverter motor controller.
What electrical wire(s) did you use go from the throttle pedal to the motor controller?

[Boxster EV]

Another questions regarding the accelerator.
Did your Boxster 986 have cable or an electronic gas pedal?
The '02 Boxster S has an electronic pedal so hopefully I can tie this directly into the Tesla Open Inverter motor controller.
What electrical wire(s) did you use go from the throttle pedal to the motor controller?

Yes, my one has an epedal as standard (hall effect). The wires you’ll need to use for the throttle control go to the Porsche motronic ecu in the boot.

Here’s the diagram to connect to the drive unit (the colours should be self-explanatory:

You’ll just need to use one set (it’s a dual pot throttle).

[canadasconvert]

Thanks for the accelerator info. That will save a lot of searching.
For cooling the major components (motor, charger, DCDC converter, batteries) I was planning on adding a single Bosch water pump to both existing radiators and piping. Have you done this? I have heard of others who have divided the cooling into two systems. One pump and radiator for the motor and charger and another pump and radiator for the batteries and DCDC converter. Any thoughts?

[Boxster EV]

Thanks for the accelerator info. That will save a lot of searching.
For cooling the major components (motor, charger, DCDC converter, batteries) I was planning on adding a single Bosch water pump to both existing radiators and piping. Have you done this? I have heard of others who have divided the cooling into two systems. One pump and radiator for the motor and charger and another pump and radiator for the batteries and DCDC converter. Any thoughts?

I tried various options regarding the cooling. In the end I settled on using just one radiator up front with a Davis Craig pump. If you do this you need to either reconfigure and weld the aluminium tubes that go front to rear underneath the car, or replace them both with standard cooling hose which is what I did. You’ll need an internal diameter cooling hoses of 19mm, they pretty much fit everything. You’ll also need a smaller diameter ventilation/ bleed hose which runs from the top of the rad to the header tank.

In terms of the cooling loop, my set up is as follows: radiator - pump - drive unit - batteries - charger and return. DCDC is air cooled. It works well. Tom DB gave me the Arduino ino to have the rad cooling fan kick in over CAN BUS but it’s never been required.

I’ve not yet installed a valve to remove the radiator from the loop when battery heating.

[canadasconvert]

What were the specs on the Davis Craig pump? (flow, head, etc.)
Was there too much pressure drop to keep both radiators in operation with a single pump?
With both radiators in service, I would need to put the pump in the engine bay. With one radiator, I could put the pump where the gas tank was, so it will be a short hose run to the DC-DC and charger.
I am also planning on using the return lines (hot) for cabin heating.

[Boxster EV]

What were the specs on the Davis Craig pump? (flow, head, etc.)
Was there too much pressure drop to keep both radiators in operation with a single pump?
With both radiators in service, I would need to put the pump in the engine bay. With one radiator, I could put the pump where the gas tank was, so it will be a short hose run to the DC-DC and charger.
I am also planning on using the return lines (hot) for cabin heating.

It’s just unnecessary and a waste of energy in my experience to use both rads. Granted it doesn’t really get hot or cold to the extremes in the UK (just generally wet), however I’ve not had any over temp issues for drive unit or charger with my set-up.

The coolant return lines will not get warm enough for cabin heating. Instead you’ll need one of these, which incidentally fits perfectly in place of the existing heater core.

Red indicates that a spacer will be required as the PFC heater is a lot smaller. I used heatproof adhesive foam.

A waterproof cover will need to be attached over the top of the heater. I used self adhesive flexible rubber roofing membrane.

Part number for pump. It’s cheap but effective.

Got it mounted in the fuel tank area along with the DCDC, power steering pump and vacuum pump.

[canadasconvert]

Thanks for the insight. For the one radiator cooling, did you cut the OEM piping and tie the rubber hose modification there, or did you tie directly into the existing rubber hoses from the radiator? There is not much room un the gas tank bay to work.
I thought you put the vacuum pump in the engine bay. That's where I have mine and I am hoping the long plastic tube going to the brake booster will act as a reservoir. I have the Volvo 3 way valve/switch coming.

[Boxster EV]

Thanks for the insight. For the one radiator cooling, did you cut the OEM piping and tie the rubber hose modification there, or did you tie directly into the existing rubber hoses from the radiator? There is not much room un the gas tank bay to work.
I thought you put the vacuum pump in the engine bay. That's where I have mine and I am hoping the long plastic tube going to the brake booster will act as a reservoir. I have the Volvo 3 way valve/switch coming.

My coolant hoses are connected to the three OEM hoses (x2 coolant lines and x1 bleed line) at the wheel well on the left hand side of the car.

There’s loads of room in the fuel tank area for all these activities. I relocated my UP28 vacuum pump there as it didn’t fit in the engine bay once I’d added the new battery boxes. I’ve removed all of the OEM vacuum lines and run a new hose directly to the brake booster. Keeps it simple and eliminates the risk of the 20 year old Porsche lines from leaking.

I need to get the car in the air this Sunday, therefore I’ll do a YouTube video showIng this.

Although, if I was doing it again and had the budget, I’d fit an ibooster and do away with the vacuum system altogether. There’ll always be something with an EV conversion that could’ve been done better with more time and money.

[Boxster EV]

Over the past few weeks and months I’ve slowly been improving the car with battery boxes, newly redesigned HVJB and PTC cabin heating. My knowledge of messing with Arduino code has also improved (although I’m still useless), largely thanks to Jon Volk’s signposting and this has opened up other opportunities to control systems within the car.

With the assistance of a friend we (he) fabricated some stainless steel battery boxes and fitted them in engine bay and beneath the boot floor. They’ve been designed in such a way that the frame system can be dropped out of the car in one piece in about 30 minutes; battery and motor attached; and a minimal amount of unplugging. This is a huge advantage for maintenance reasons. I just need to find some decent quality shut-off valves for the coolant lines so the system doesn’t need to be fully drained each time. I’m also on the hunt for some reasonably priced IP rated HV plugs so that I can easily disconnect the front battery upon removal of the frame system.

This picture shows the largest of the boxes and the strengthening at the base, which bolts into the frame system below it. Copper battery terminal bus bars were fabricated to reduce the need to contort the HV cables and help when paralleling the packs together (the boxes are rubber lined). We also integrated small bulkhead into the lower box to accommodate the coolant lines. The bottom lid is welded to the box above it.

Unfortunately, during the installation it was unforeseen that that the handbrake cable would not fit around the outside of the battery boxes and therefore a bespoke cable was ordered at a stupidly expensive price – this delayed things a week or so. I took the opportunity to replace the brake shoes at the same time, which complimented the recent service on the drive shafts – new bolts, boots and CV grease.

Lower box in situ with no lid yet to be fitted (The lids attach with M6 bolts.).

This picture shows two battery boxes in situ inside the engine bay. Before production we were careful to measure all of the dimensions accurately and this paid off as there’s about 10mm to spare between the top of the box and engine bay cover. I can categorically say this wasn’t a fluke.

Underneath the car looks like this: The rear box houses the second mid-size battery brick and is welded into the boot floor of the car. I’ve not included a picture inside the boot at I’m still working on the rats nest of OEM LV wiring and waiting for my mini VCU to arrive. The Porsche DME motronic system still needs to see some signals in the car in order for the ignition and auxiliary power management to function, therefore going through the process of depinning and removing the unwanted ICE elements of the car’s harness is painstaking. Trying to make the conversion as clean as possible therefore didn’t want to stuff unwanted wires out of sight and forget about them.

One thing that I hadn’t considered is whether my HVJB would fit in the engine bay after stuffing it full of batteries - It doesn’t in the current form factor, which was a bit of a blow, meaning that I had to knock-up a smaller one, and I spent a whole day doing just that. However, because I’m an idiot, I wired the LV side in such a way that enabled the DC2DC under load before closing the main contactor (and left it like that for about 30 minutes pulling current through the pre-charge circuit) and melted the side of PVC HVJB that the pre-charge resistors were bolted to - I could have cried. Therefore, I’m now onto HVJB V3 with both DC2DC and PTC heating only enabled after the main contactor closes. You live and learn. But hey, at least the DCDC HV is connected on the OEM side of the contactors, right, Arber333?

HVJB V3:

[Boxster EV]

Moving on to the cabin heating, I sourced a PTC heater from EVWEST that fits perfectly into the aperture of the car’s original coolant based heater core. Following some help from Zero EV, I’ve actually got it working via the car’s OEM digital climate control panel (analogue signal sent to Arduino to close relay → to close HV contactor) – it’s fairly simple, but does the job – need to just wrap fan speed signal into the equation. Here’s a few pictures showing how neatly it fits (Waterproof membrane and cowling not yet refitted):