Ever wanted to make your own electric car? If you’re like us, chances are you always dreamed of one day opening up the hood of your old ride and fixing it up with an electric motor. For many electric car enthusiasts, this remains just a dream for most as many do not believe they have the money or the expertise to get the job done.
That’s why it shocked us to find that building your own electric car is nowhere near as expensive or complicated as so many make it out to be. Essentially, all you need is a little car know-how, about $2000 lying around, maybe a trusted mechanic to supervise at times, and a little bit of sheer determination. Got those? Great, then let’s get started.
Why Build Your Own EV?
When I decided to first build my own electric car, I had no idea what I was getting myself into. Like most people, I assumed I’d be in for an enormously costly project, weeks of elbow grease, and a headache known only to the most seasoned of mechanics.
To my surprise, that was not what I ended up with. Rather, all it took was a weekend, a couple phone calls to my mechanic buddy, and a little bit of hard work. Oh, and about $2,000 US worth of car parts, but we’ll get to that later.
The simple reason to build your own electric car is that it’s a whole lot of fun. I mean, what could be better than spending a sunny Saturday afternoon with your head under the hood of your old BMW 528i? If that sounds like paradise, then a DIY electric car should be next on your list of personal projects.
Aside from the fun factor, building an electric vehicle will save you money in the long-run, and it is a truly rewarding experience in and of itself. By ditching gasoline, you won’t need to pay at the pump every week to refill your daily commuter. And also, the feeling of bringing a car to life due to your own hard work and perseverance is a beautiful feeling unlike any other.
So what are you waiting for? If you have some extra cash lying around, can tell apart a transmission from a flywheel, and are willing to get your hands dirty for a weekend, then this is the DIY project for you. And luckily for you, our handy guide will simplify everything so you don’t need to sweat the small stuff along the way.
Electric Car Kits: Right for You?
Electric car kits to build your own converted electric car are taking the market by storm. And we’ll be honest: they are awesome for their simplicity and convenience.
However, we often do not recommend them as they tend to be significantly marked up from their a la carte price. Also, we find that using these kits can sometimes take away from the fun and adventure that comes with finding all the right parts yourself.
If you do decide to go with a conversion kit, you certainly benefit from peace of mind. This is because most kit sellers provide technical support with the purchase of every kit. So if you have any doubts in your ability to pull off the job, you can rest assured that someone will be available to help you over the phone if you run into any sticky situations. And unlike scrap yards, most kits also come with warranties and refund policies.
We found that Canadian Electric Vehicles Ltd. has some beautiful kits available for both AC and DC electrical systems. Likewise, EV West also sells premium conversion kits for classic Volkswagens, Porsches, and Toyotas.
Tips for Buying the Right Conversion Kit
Below are some quick tips and hacks for finding the perfect conversion kit, and sorting out the duds.
- Never buy “universal” kits; always find a kit specific to your base model’s transmission
- Always choose a seller that offers a full refund or return policy
- Never buy a conversion kit for a 4×4—they’re simply too heavy
- Whenever possible, don’t buy a kit for an automatic transmission—they tend to limit your electric vehicle’s range
- Check out this helpful video for a basic walkthrough of an EV conversion kit
How to Build Your Own Electric Car
Figuring out how to build your own electric car starts with understanding the basic anatomy of an automobile. This means knowing what base model is best to work with and why.
That is why we advise taking the time to first familiarize yourself with the ins and outs of a vehicle so you don’t run into any issues along the way. That means being able to tell apart every component, from a motor and transmission to a coupler and flywheel.
The Donor Car
A general rule of thumb is to select a light car with a manual transmission, as automatics tend to seriously drain your batteries’ range. This means no 4x4s, as they typically add too much weight and drag for the batteries to support over longer periods of time.
Personally, we recommend choosing something sleek and lightweight such as a E39 Generation BMW, or an old Volkswagen Santana. This will help maximize battery life and range. Once you’ve found the perfect car, then it’s time to get down and dirty by stripping it of its engine, exhaust, muffler, and gas tank.
The Adapter and Coupler
Next up is the adapter plate and coupler. Usually, these are bought and sold as a package deal. These pieces will be housed under the hood where they will bolt onto the electric motor and the transmission. This requires anywhere from 6 to 10 bolts to securely fasten them.
And don’t be fooled by their small size. These guys are critically important for building your own electric car. This is because they connect the existing transmission to the new engine. So while they’re little, they have an important job to do—so don’t cheap out on these.
The controller is a more expensive piece of machinery that will ultimately control the amount of voltage that your motor receives. If you’re confident in your soldering abilities, you can even make the controller yourself. However, this is a super technical task, and even soldering one wrong diode can ruin a capacitor and turn the whole thing into junk.
Since it’s a little risky to handle the controller all on your own, we recommend either buying one pre-made for your specific transmission or getting a professional to assemble it for you.
Now we’re getting to the good part. When it comes to choosing the right motor, all you need to look out for is a series wound DC motor. AC systems also work serviceably, but we find that you can get a little extra mileage out of a DC unit.
Surprisingly, this selection is one of the easiest you’ll make throughout the conversion process. The general rule when it comes to motors is to find a rust-free DC system that weighs approximately the same as the engine that was in the car beforehand. This ensures that the weight distribution and balance will be proper in your new car.
Lastly, we have the batteries. For these, you’ll want to go with no less than 72V combined. Personally, we used a row of 6 large-cell 12V batteries and laid them in a metal tray fastened next to the motor. And remember to always opt for new batteries as used models tend not to last.
Then, get yourself a power inlet to replace the gas tank and a regular old extension cord for overnight charging. Once it’s all thrown together, you’ve got yourself a snazzy new electric car. That wasn’t so bad, now was it?
What’s the Cost?
“How much does it cost to build an electric car?” Here at NoFillUp, we’re asked this question just about every day. And since the answer varies so much depending on the model of base car used and the builder’s level of expertise, it is hard to quote an exact price.
Instead, we will itemize each component of the DIY electric car by price, and add in the expected cost of one or two trips to a mechanic (Hey, nobody’s perfect!). Check out our breakdown below for the most comprehensive piece-by-piece cost estimates in US dollars.
- Conversion Kit (Optional): $6,000-9,000
- Base Vehicle: $500-1,000
- AC/DC Motor Controller: $500-900 (Used)
- Charger Unit: $400-500
- Adapter and Coupler: $400-600 (Used)
- Electric Motor: $500-1000 (Used)
- Lithium Batteries: $500 (72V)
- Nuts and Bolts: $100-200
- TOTAL: approx. $2,350
That was a lot to take in. We get it. That’s why we assembled a quick list of the most essential takeaways described in more detail above.
- Pick up an old junker, preferably a late ‘90s model with a manual transmission
- Gut the car of the engine and all things related to gasoline and emissions
- Purchase a used adapter and coupler online and install each
- Find your base model’s electrical controller and properly install it
- Purchase an AC or DC electric motor and install it under the hood
- Set up a tray next to the motor and supply it with no less than 72V worth of batteries
- Hook up a power inlet and cover where the gas tank once was
- Use a regular extension cord to charge the batteries overnight