Before I start with anything, I need to have estimates on two major points:
- Costs for motor, battery and labour
- Final mass of the vehicle
The first one is obvious and the second one influences the first, because if the car gets significantly heavier, I will need to adapt the suspension.
I am going to replace the engine, transmission, exhaust, tank etc. with the electric drivetrain. Let’s assume a maximum of 80 kWh. Will I need to replace springs and dampers, tyres etc.?
Here are some numbers I came across – with the help of AI (Perplexity Pro):
| Removing | mass |
|---|---|
| XK engine 3.4, oil, accessories | 320 kg |
| Gearbox and Overdrive | 90 kg |
| Clutch, Flywheel, oil | 32 kg |
| Radiator incl coolant | 32 kg |
| Exhaust system | 45 kg |
| Petrol tank and pump assembly | 30 kg |
| Petrol (54l) | 40 kg |
| Starter, dynamo, cabling etc | 20 kg |
| Total | 609 kg |
| Adding | mass |
|---|---|
| Electric motor (EMRAX 268) | 22 kg |
| Adapters | 15 kg |
| Inverter and MCU | 8 kg |
| HV Battery 80kWh | 530 kg |
| BMS, switches, security, fuses | 15 kg |
| Charger & CCS | 25 kg |
| DC/DC | 6 kg |
| Cooling system incl coolant | 35 kg |
| Vacuum pump, accessories | 30 kg |
| 12V battery & cables | 15 kg |
| Total | 701 kg |
That’s 92 kg more for 80kWh – not too bad. And I took a conservative approach with 180 Wh/kg for the battery (NMC, Lithium-Ion), which should be possible to beat.
I will assume no changes are required to the suspension then.
The total mass of the car will be 1583 kg empty an 1933 kg with 4 people and luggage.
Let’s talk about money
This is going to be very high level and for the basics only. I am not going to add any interiour changes or any other modernisation I might decide to go with. I just need to know how many banks I need to rob 🙂
| Assembly | Costs (€) |
|---|---|
| Engine, e.g. Emrax 268 | 14,000 |
| Inverter & MCU | 10,000 |
| Battery 80kWh, BMS | 30,000 |
| Housing, Security, Fuses etc | 10,000 |
| Charging System | 3,000 |
| Adapters, coupling systems | 6,000 |
| Documentation, registration | 3,000 |
| Labour | 30,000 |
| Total | 106,000 |
I knew it won’t be cheap, but more than 100k for the basics is a little unexpected.
This is AI, I hope there are many mistakes and I can get some components cheaper with the company that hopefully has some goo sourcing options. I don’t necessarily want to go with used components and I really don’t want a Tesla drive unit, although I know it might be cheaper.
Whatever I can source in Europe (not US, not China) I will try to.
Performance
How much power and torque make sense, how much do I want? I don’t need a performance car, however, it should not be slower than the original. Does it mean the additional torque from the motor might damage the propshaft, rear axle differential or drive shaft?
The Emrax 268 electric motor is an Axial flux motor and offers 210 kW and 500 NM of torque with 101 kW continuous power at 68% efficiency. It can be combined with the Cascadia CM200DX inverter in a 400V environment.
Leave a Reply