Curbside Classic: 1971 Austin FX4 Electric Conversion — Keep Your Tesla, Guv’nor

fx4 electric front 3_4a

While not exactly common sights on American streets, classic English taxis do show up on this side of the Atlantic from time to time. So, aside from being in fairly nice condition, this Austin FX4 cab, recently spotted under rather British weather conditions in Elizabethtown, PA, might not be worthy of much note. But wait, there is something a little unusual…fx4 electric front fender

…the script on the left fender (or should I say wing?) reads “Electric”. I had no idea there were battery-powered versions of these cars. Except there aren’t. FX4s (built 1958 to 1997) were powered by a variety of small diesels, and as far as I can tell no factory straight electrics (nor hybrids) were made. So what’s the story here?

fx4 electric rear 3_4

You have to love the Internet. After a bit of research, I discovered the web site of a guy in nearby Lancaster, PA who is bananas for the perceived environmental benefits of electric vehicles, and who masterminded the taxi conversion. This is actually the third such vehicle turned out by his shop, following on from earlier conversions of a Saab 96(!) and Mazda Miata. Here’s a shot of the Saab, because one can never have enough pics of old Saabs, electric or not:


Tasteful, no? Apparently, the London taxi build was mostly facilitated through award of a components package when one of the builder’s earlier vehicles won a 2011 contest for gas-to-electric conversions.

fx4 electric front

According to my reading, the conversion project took about four years to complete. Although the car appears more or less stock externally, much more had to be done than simply replacing the (broken) 2.5 liter Leyland diesel with an electric motor and stuffing in some lithium-ion batteries.


A total of 50 Li-ion cells,  under bonnet and boot (28 front, 22 rear) provide the motivation for a NetGain WarP 11 (yes, that’s how it’s spelled) DC motor; apparently this is a popular choice for these types of conversions. While I’m a bit shaky on the power calculations, it appears the motor will handle up to about 170 volts, outputting around 110 peak HP; continuous rating is approx. 35 HP at 72 volts. To get the power to the wheels, the (also broken) Borg-Warner automatic transmission originally fitted has been exchanged for a T5 manual from a 1990 Mustang.

Aside from the drivetrain modifications, the most time-consuming structural changes included fabricating new mounts for the electric motor and transmission, constructing the boxes for the batteries, adding air-conditioning, fabricating a new dashboard and console, and replacing the brake lines and wiring harness. There was also a lengthy wait for delivery of a custom-made adaptor plate for the transmission.

fx4 electric interior

Sorry for the poor visibility of the interior. The original (and flimsy) plastic fascia has been replaced with one fabricated from part of the tailgate from a Chevy station wagon, to support additional components such as control boxes for battery heaters. Although the old automatic shift handle and telltale remain present, a floor-mounted shifter appears to have been installed.

fx4 electric rear

Aside from the “Electric” badging, the only other really noticeable external change is conversion of the old fuel filler to a plug-in receptacle. I was unable to find any stated range information, but the Saab and Mazda apparently can run about 100 miles with fewer cells, so the Austin should be good for at least that.

All in all, a fairly clean installation (in all senses) and the builder deserves credit for keeping visual changes to a minimum.

If you’d like to see more of the nuts ‘n’ bolts aspect of the conversion, a series of videos on the project can be found on YouTube: search under  “electric conversion of a London Taxi”.

Additional reading:

Paul Niedermeyer on the original FX4