What are the steps in converting a classic car to EV?

Begin with a vehicle to convert

Ideally, you will have a pre-1990 vehicle in good condition. Newer vehicles often have complex electrical systems that may not be compatible with an EV conversion. To get your vehicle registered, you may need to get rust removed and bodywork fixed up. 

Understand your expectations

Do you plan to use the vehicle for your daily commute? Do you plan to go on expeditions into rural and remote areas?  How important is speed and acceleration to you?

Commercially produced electric vehicles are designed from the ground-up to optimise range and performance: they use special low resistance tyres, aerodynamic bodies and suspensions designed for the weight of heavy batteries, and complex electronics to enable fast charging. 

Converted classic cars are always going to be a compromise because you will be working within the constraints of a car designed over 40 years ago.

Set your budget

Converting an old car is unlikely to be cheaper than a new electric car with comparable performance or range. Be prepared to budget for a distinctive and quality end-product.

Design the optimum conversion for you

Find a designer who is prepared to work with you to get as close as possible to your performance and range expectations within your budget and the constraints of your vehicle and the vehicle licensing regulations.

DIY or get someone else to do the conversion?

Getting someone else to do your conversion may be an easier option, but will be more expensive, and the company may not be prepared to follow your design.

If you approach a company to do the conversion, check with them:

• are they prepared to follow the design that has been optimised for your vehicle?  A sure sign that companies have limited expertise and design skill is that they try to force you to do things their way. For example, some companies specialise in using second-hand Tesla battery packs which they are familiar with, and will be unwilling to use other kinds of batteries because that will involve learning about different battery and motor control systems.

• are they prepared to provide you with a detailed design that precisely specifies the design options considered and performance implications of each design option?

• if the company insists on using second-hand Tesla batteries, do they pull the battery pack apart to remove cells that have reached the end of their life? If not, you are likely to have ongoing problems with your battery.

• how long will they provide warranty for the components and workmanship?

If you decide to take the DIY route, prepare yourself, and assemble a team to help. For example, companies that supply batteries and equipment will often do the battery wiring and battery installation for you. You will need to be prepared to get components fabricated to the design provided to you by the designer.

Conversion process

Assuming you have decided on the DIY approach, the process will involve the following steps:

1. Advise the State Government motor vehicle licencing department that you intend to convert your vehicle to electric operation.

2. Remove the components you no longer need - engine, exhaust, cooling system. Depending on the design you may retain the parts of the transmission system or may remove it all. 

3. Get the body fixed up - remove rust, repaint, fix upholstery

4. Order components required - batteries, motor, controls

5. Get the electric motor mounts fabricated. The motor will need mountings to hold it in place.

6. Get the battery boxes fabricated. 

7. Mount the motor into the vehicle and link up to remaining transmission components.

8. Contact an engineer certified by the State Government motor vehicle licencing to inspect the vehicle and record progress

9. Ensure the battery boxes fit into the remaining space in the vehicle. Get the battery supplier to install batteries into the battery boxes, along with all of the wiring for the battery chargers, battery and motor controls and power supply to the motor.

10. Install 12V electric powered components for air conditioning, power brakes, power steering and reconnect the remaining 12V system from the original vehicle - lights, indicators, horn, and wipers.

11. Contact an engineer certified by the State Government motor vehicle licencing to inspect the vehicle and record progress

12. Begin testing the vehicle to ensure everything is working

13. Depending on details of the conversion, you will need to address instrumentation and controls for the vehicle. If you have retained the original transmission system you can re-connected the speedo, otherwise will need to use an electronic speedo that will need to be calibrated for your vehicle. Likewise, you will need to work out how to turn the system on, select forward and reverse, and monitor battery status.

14. Once you have completed instrumentation and controls, you need to organise for your vehicle to have a dynamometer test to ensure the power output complies with the motor vehicle design rules. You will also need to have the vehicle weighed to ensure weight and distribution of weight are within the design rules, otherwise you will need engineering reports to certify that the vehicle is safe to drive.

15. Contact an engineer certified by the State Government motor vehicle licencing department to inspect the vehicle and report on whether it is ready to be registered.