I have 'lurked' for quite a while on this site but thought it time I posted.
I'm the technical director of Classic Retrofit
- we make upgrade goodies for classic cars, particularly Porsches. In the last couple of years we have redesigned ignition units, fuse panels and other parts for these cars. We have also designed an aftermarket electric air conditioning system for classic cars. I monitor the EV world closely to see what tech can be adapted to classics and naturally drivetrain is the next step!
Two years ago I purchased a Porsche 914 from California. It had already been converted to electric power a few years previously. You could call it a vintage EV conversion. The spec was as follows:
42 x CALB Thundersky 180A cells
FB4001 motor adapted to manual 5 speed gearbox
Curtis 1231 controller.
Bogart Engineering 'Trimetric' SOC meter (must be vintage!)
I knew the tech was a little out of date but the car was solid and a very good price so I thought it would be a good starting point. I had it shipped to the UK and amazingly it switched on with 99% charge and it drove along quite ok (albeit up and down my driveway).
In order to learn, I thought I'd strip the car and build it back up. There were some 'interesting' features. E.g. an undertray that was serving to store falling leaves and pine needles and about a mile of wiring, all the same colour - pink! It was a mobile tinder box so I am quite glad I took the decision to give it a refresh!
Plan A consisted of keeping the batteries and motor but updating the controller and the charger. I bought an Evnetics Soliton Jr off a guy on here and a couple of bits from the States. I ran the orange DI cable and started to remake the battery boxes.
We suddenly got very busy with the electric air conditioning systems so the project has frozen rather. Since I've been away, the tech has moved on again so I am now considering a different approach using Tesla parts. I need a little guidance:
Once the engine, transmission and fuel tank have been removed and with some 'lightweighting', I can get the rolling shell down to around 750kg
I have read that each 5.3kWh tesla battery pack weighs around 25kg and that the large Tesla rear Drive Unit weighs 132kg. The small DU weighs 88kg.
Ideally I would like a 200 mile range and sports car performance if required. Not insane (like that Evora) but need to keep up with old 911s (0-60 in 6 secs)!
So my first questions are:
1) How many battery packs should I aim for? I can accommodate 8 quite easily but 6 would be lighter obviously.
2) What would be the battery configuration for 6 vs 8 cells?
3) Am I crazy going for the large DU or would the small one give me adequate performance?
p.s. Happy New Year!