Voltage Stepper Relay RackVariable Voltage/Current ChargerVoltage Stepper Relay ControlStepper Rack InstallationMotor CompartmentMotor CompartmentRear Battery BoxResistance ControllerAlternator Installation
OwnerMike Sargeant
LocationTempe, Arizona United States map
Email email image
Vehicle1972 Chevrolet Vega 2300
a 2-door hardtop purchased in March of 1980. No power steering or power brakes.
MotorBaldor 7544D Series Wound DC
new, 8 HP @ 3400rpm, 72vdc 6kw, 145lb, paid $640
Drivetrainrear wheel drive, in line 4 cylinder gasoline engine, 3 speed manual transmission
Controller N/A
first I used Ford starter relays activated by a diode matrix to provide 3 voltage steps from the 96v pack, then I switched to stepped resistor control. Manipulation was first by foot through accelerator pedal then by a through-dash control rod to the controller in the motor compartment. The resistance controller was extremely smooth with 6 steps. If a vehicle has a low top speed as did mine, the resistors are cut out rather quickly so none are in the circuit at speed to cause losses.
Batteries16 Trojan EV4 or equiv 220AH (EV106), 6.00 Volt, Lead-Acid, Flooded
top terminal, screw cap, about 60lb each
System Voltage96 Volts
Charger N/A
FWBR driven by a 2510CT STACO variable transformer so as to vary the applied voltage & thereby the current to the various pack voltages I experimented with (48-72-96) & an old 12VDC unit for accessory voltage
HeaterPhoenix Valley of the Sun solar
DC/DC Converter N/A
used existing 12v car battery
InstrumentationAmmeter & voltmeter plus car's speedometer/odometer
Top Speed45 MPH (72 KPH)
never that curious about top speed, got to 45mph in 2nd gear once but ran out of clear road though was still accelerating
Accelerationpoor at any gearing, not nimble enough in traffic for safety, usually drove it at 25 to 35mph
Range44 Miles (70 Kilometers)
strictly a to and from work car but battery condition at end of each day indicated that this was the maximum that could be had before exceeding the cell minimum specific gravity.
Watt Hours/Mile200 Wh/Mile
varied depending upon battery condition
EV Miles
Start:45,666 Miles (73,476 Kilometers)
Current:48,649 Miles (78,276 Kilometers)
Total:2,983 Miles (4,799 Kilometers)
Seating Capacity1 adult
Curb Weight2,160 Pounds (981 Kilograms)
Curb weight as gasoline vehicle. Running weight as EV was 2539 lb as I removed all weight possible. My estimate of scrap body weight was 1273lb. The scrapyard paid me for 1300lb.
TiresA78-13 run of the mill for that make/model
Conversion Time4-1/3 months
Conversion Cost$3282. Varied up & down as I experimented with an on-board gasoline generator, bought and sold various components at end of experiment.
Additional FeaturesNone, this was an experimental platform, & was quite ugly. I put nothing but homemade parts & body work into it with no intention of dressing it up to impress anyone.
The motor blew & was replaced under warranty & was sold new. Also a friend bought the engine & the batteries were sold for 1/2 price as almost new.
The $3282 cost included savings over driving my 69 Ford wagon to work for those miles.

code by jerry