Q&A Converted Ford Fiesta – Electric Speed Shop


I am a self proclaimed electrical nerd. Started with car audio in high school, degreed in electronics engineering, career electrical engineer (17 years?). Started building drones a couple years back. I knew about EV conversions back in 2002 but the lead acid ba eries were horrible so li le interest grew. With the availability of Lithium the interest was renewed watching Jehu Garcia and EV West.

Why did you choose a Ford Fiesta for your conversion project?


The Fiesta chose me. I had been keeping tabs of Craigslist for a few months looking for someones old project so I could get a jump start on a conversion and play with the equipment. Found this for $500 in Tacoma and went down to get it. It had 8ea giant red top lead acid batteries for a 96V setup, ancient military starter/gen motor, a tiny kelly controller, and some marine grade chargers. Really rough but it moved. Could go about 4 miles before the batteries were toast. Needless to say, everything was ripped out.

What was the original design for your conversion and how long was that design process?

Short version: Keep the system series DC to keep cost down. Off the shelf AC systems are excessively expensive. On and off it took me a few months working part me on it.

Less short version: The original design was to keep it simple. The easiest EV system was/is a DC series motor so I started looking. Happened to meet up with David Cloud (recently passed) here in Seattle and picked up an older ADC 8” motor with a known good 12600 kelly. The hardest part was getting the motor adapter and plate designed/made. Found the bolt pattern for the Fiesta engine and the motor online so I drafted up a motor mounting plate. Had my friend laser cut it out of 10 gauge steel and layered three of them up to make the plate, about 3⁄8” thick. Found a keyed industrial flange and cut it down and then had a couple of pieces cut to mate the transmission shaft. Welded those together and it mated right up!


For the electronics all I needed was the batteries, charger, EVSE, and hardware. Got a good deal on Fiat 500e batteries through a company Jehu Garcia recommended and got 18kW total delivered to my house. Found that ThunderstruckEV had a complete TSM2500 kit with EVSE so I bought that.

Has your Fiesta been updated from that original design in any way? Did the deviation occur while building or after better technology became available?

Yes. After I got it all together and put about 200 miles on it I had a revision. I thought I could bottom balance my batteries to avoid a BMS but since they were grouped in 5S strings, this posed a big inconvenience. I bought a used 108 cell Orion BMS, installed and configured, and have been happy with it.

How long or how many hours were put into the build, from removing the first internal combustion engine (ICE) component to driving with battery power?

As my car was bought without the original engine in it, hard to tell. I also spent months just thinking about things and sourcing parts. I would say it took about 80 hours of labor over 8 months.

If you had to chose one part of the conversion that was the “most difficult” what would that be? How about the “easiest”?

Easiest would be the wiring, but that is kinda what I’ve always done. Hardest thing would be getting the motor mounting and adapter followed by the battery racks. I’m not a metal fabricator so the racks took me a little bit to figure out.

What electric components currently power the Fiesta?

Currently an ADC 8”, kelly 12600 (120V 600A) controller, 12kW of Samsung Bosch Fiat 500e batteries configured in a 30S2P pack (64Ahr cells for a total of 14.6kWh), Thunderstruck EVCC and charger, Orion BMS (non-CAN to the EVCC), J1772 port.

How did you choose those components? Were any chosen to help achieve a specific goal?

The motor controllers determined the pack voltage, everything else was sized accordingly. Ideally I wanted to be able to drive back and forth to work on one charge so that determined the pack size.

Can you provide us the final specifications on your MK1 Ford Fiesta?

At 268W/mi on my very hilly commute with 14.6kWh installed, about 54 miles max. No clue on 1⁄4 mile me, max charge time is about 6 hours at 9 miles per hour charge, weight is likely near the original at 1400 pounds (only 240 pounds of batteries).

Any planned upgrades or changes to the Fiesta? How about another conversion project?

The one update I really want to do is to make my own motor controller. The old Kelly won’t pass more than 60A of current at stalled rotor. Since it needs to do burnouts, I need to update this.

How can people reach out to you for more information or follow you & the Ford Fiesta?

Sure, I have most of my data on EVAlbum but am looking to update Twitter eventually. Email is the best contact at tdshorten@gmail.com .

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Record holding Ford Fiesta!

So, the DIY EV crowd is a very supportive and helping crowd. I started researching the day I brought that Fiesta home to try to figure more about the car and the conversion. In doing so, I found the original EVAlbum entry for my car. It was owned by a Joe Smalley, here locally in the Sea le area. A search lead to me finding that the car was originally converted in the 90’s (hence all the old gear and wiring) with the help of Rich Rudman! I gave Rich a call and he confirmed that he did that and the used it to drag race, perhaps before NEDRA got its start.

I had been given the name of John Metric at LoneStar EV to find some fuses and ask him about the Orion BMS settings. Off chance, he asked my about my car. After a quick search, he found that my car still has the national record for the standing 1⁄8 mile for the 48V class. I was fairly amazed that the record has stood for such a long time, yet here it is in my driveway, with a significant piece of history intact.