EV Conversion Project
I've been interested in electric vehicles for quite some time, both personally and professionally. Working in the tech industry, I was meeting Tesla devotees from their early days. Researching the future of energy for CMS back in 2016 really cemented for me that our energy future was purely electric. And then the foresight project I undertook with Auto Trader on the future car in 2019 led me to a lot of the work that was going on to convert existing petrol engined vehicles to electric, with open source components.
My personal interest in cars goes back way beyond that. I'm not particularly into speed or racing. But cars are such a big machine that they were always going to fascinate a geek like me. This fascination has been passed to my daughters and particularly my eldest (who hasn't decided yet if she wants me to name her here). Watching Car Masters: Rust to Riches, and then the tours of the Petersen Museum in California together, she developed a real passion for retro cars. And so, a project was born. Could we together take an existing vehicle, convert it to electric, and give it some of that retro style?
The loose plan is to build an electric drive train that can then be dropped into a small, cheap but (relatively) modern sportscar. And then to do a body conversion on that to give it some of that retro style. This is a big project so I'm going to take it step by step rather than assuming we will be able to achieve all this. This isn't going to be a build blog. More of a place to document what I learn and the details of our chosen components. As (if) it gets closer to completion then I will add more blog-style elements and videos.
For all the fantastic information and help I've found on the forums, I've still struggled to find answers to a lot of questions when first getting started with this project. So I thought it would make sense to document the answers here in case it is useful to others.
How do you choose the right components?
As noted above, my initial parts selection was originally based on a whim. It may prove to have been a mistake but it got me started. When I have a better answer than just hitting "Buy It Now" on something that takes your fancy, I'll put it here.
How much power do you need?
I'm hoping that rule of thumb from the forums above is accurate: 35kw/metric ton is your baseline. Anything above that gets progressively more... exciting. TBC!!
How are you going to connect it all to the donor car?
There are lots of choices here and the one you choose will determine what complications you have down the line. I have chosen to mate my motor up to the existing gearbox on a rear wheel drive car. That means everything from the gearbox back is standard, but I have to make up an adaptor for the flywheel and a plate to match up to the gearbox bellhousing. I coud have chosen instead (and might yet) to use the gearbox from a Lexus GS450H, which contains two electric motors and kicks out an apparent 300 horsepower. In this case, I would instead have to mate the back of this gearbox to the propshaft. Some people take out the clutch and bolt the electric motor straight to the input shaft. Some people do away with the gearbox altogether. It all comes down to your component choice, but every decision changes the complexity of the project down the line.
How are you going to control it?
The obvious choice here seems to be buying a board from EVBMW/OpenInverter but there are lots of other options...
EV project by Tom Cheesewright is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at http://projects.tomcheesewright.com/ev-project.html.