When it comes to me and cars, there have been two consistencies throughout my lifetime:
More recently, say in the past 10 years or so, I’ve also wanted to build an electric car. When I recently realized that there are plans available – for free, no less – on how to build your own Lotus Seven (know as a Locost – combination of “Lotus” and “low-cost”), I thought, “Eureka! I can kill three birds with one stone! I can build an electric Lotus Seven!” And thus some voracious reading and searching began.
At first my only point of worry was whether I’d use a transmission or not. With DC motors, a transmission is retained, and two gears (one for around-town, one for highway, generally 2nd and 3rd) are used. Of course, part of the allure of a Seven/Caterham/Locost is its extreme light weight (a typical weight is around 1200 lbs, or about HALF of a typical small sedan), so I started trying to figure out how to ditch the transmission and, by extension, drive shaft. In my reading on electric vehicles, it seems that the vehicles that use direct drive – that is, the motor hooked up directly to the wheels with no
intermediate gearing – use AC drive motors. Ouch. A good DC motor can be had for $3k new, but the same thing in an AC motor? Triple that.
This lead me to start thinking about the cost of building an electric Locost. Not only would I be looking at either an expensive (DC) motor, or a REALLY expensive (AC) motor, I’d still have to buy the batteries for it as well. I’m still holding out hope for EEstor and their EESU, which promises an order of magnitude of improvement on the weight and cost over a comparable lithium-based battery. My feverent wishes notwithstanding, the EESU is still vapourware right now, so there’s no point in planning a car around it. Thus, I’d be looking at either lead-acid batteries (heavy, and still not cheap), or lithium ion batteries (lighter, but still very, very expensive). Suddenly my electric Locost didn’t seem like the inexpensive way to get into an electric vehicle anymore. (Further realization: NO electric vehicle is cheap to get into right now, if you want highway capability and decent range.)
I started pondering about building the vehicle anyways, just with a gas engine in it that I could later swap out when electric drive trains and batteries are more affordable. This gave new life to my fledgling idea, but presented new issues.
As the Lotus Seven was designed in the 1960’s as a minimalist sports car, it is inevitably a front engine, rear wheel drive vehicle (also known as FR layout). Thus, to make one yourself, you need to find another vehicle of the same configuration to be the donor – you strip everything off the vehicle, and lay it out in the frame of your Locost. (Alternatively, you can get all the pieces you need piecemeal, but that is much more expensive that simply using a donor vehicle.)
Now, if you’ll think about it for a second, you’ll realize there aren’t a lot of FR vehicles out there today, especially with manual transmissions. (I am unabashed in my love of manual transmissions, and even moreso if I’m going to be making a sportscar. Automatics NEED NOT APPLY.) The vehicles that the original Locost was based on were out of Europe, and not available over here. That leaves us North Americans looking for suitable donors, such as old Corollas, Miatas, some of the rarer FR sedans, and of course small pickup trucks and SUVs. Not a lot of choice, and finding a suitable donor at a decent price is a matter of persistence, patience, and luck.
During all this research and donor deliberation, a friend of mine from highschool pointed me in the direction of the LocostUSA forums, where Locost builders of all sorts from across North America (and beyond) gather to share information. Boy, what a wealth of information there!! Not only do they share information about their finished and ongoing projects, but they also encourage “non-traditional” build logs as well. A few such builds caught my attention… and sent me off in yet another direction.
To be continued…