Recently I’ve been thinking an ideal family engineering project would be an electric car conversion. A bit of googling reveals that this is not outrageously expensive and is well within the realm of our abilities and tools, though it will provide an excuse to buy a welder.

The primary components are:

• Donor vehicle (engine optional)
• Electric motor
• Controller for the electric motor
• Adapter plate to mount the electric motor
• Coupler to connect the motor to the transmission
• Batteries
• Charger for the batteries
• Mountings for the batteries
• Miscellaneous potboxes, shunts, contactors, wiring and connectors.

Step one is to decide on the application of the vehicle – what will it be used for? EV conversions, at least the affordable kind we are thinking on, are limited in speed and range. We live in a fairly small California town without much in the way of gradients, so an EV with the ability to make two across town round trips a day would make it an adequate runabout for the elder teenager who just hit driving permit age.  That is 25 miles on the flat with a max speed limit of 45 mph and mostly only 30 mph. Not unreasonable, and eliminates possible teenage drag-racing tendencies.

What vehicle to use?

A 1971 to 1974 Volkswagen  Super Beetle.

Why?

• Beetle conversions are common – full conversion kits are available.
• Beetles are common – the largest production run of any car, over 22 million from 1937 – 2003. While in some parts of the world they have largely rusted away, here in California they putter on forever.
• Huge parts availability.
• Easy to work on – the whole body comes off the frame with about 20 bolts.
• Lightweight.
• No power steering – without a constant running engine in an EV there is nothing to drive the pump.
• No power brakes – without the Infernal Combustion Engine intake there is nothing on an EV to generate the vacuum.
• Affordable. There are always several runners available on the local Craigslist for under $2000. They are not old enough or rare enough to be collectible.
• Big parcel shelf behind the rear seat to put batteries in.
• Super Beetle (1971 on) has lots of room in the front for more batteries.
• Super Beetle has strut suspension that should be easier to beef up to support the battery weight than the torsion bar suspension on the standard Beetle.
• Pre-75 Beetles are exempt from smog, making the paperwork simpler at the DMV.
• They are CUTE!

There are some drawbacks though:

• Drum brakes. Upgradeable to disks, and there are kits to provide vacuum boost electrically. With the extra weight of the batteries this is a big concern.
• No airbags, crumple zones or any modern safety gear beyond seat-belts. Hopefully mitigated by limited speed.
• At 26-29 years old there will be wear, tear, rust and fatigue to deal with.