The EV conversion
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Motor Selection

I joined the Australian Electric Vehicle Association (AEVA). The Geelong sub-branch has helped me convert the Imp. The members suggested using a used Toyota Prius Electric motor and differential minus the ICE. The conversion would replace both the original engine and gearbox. It would require modifying the drive shaft between the unit and the wheels. However, it was not suitable as the Hillman Imp gearbox under the rear seat. Prius drive chain was too tall. Another option was to use the Toyota RAV4 hybrid rear motor on the 4WD model. This unit contains an electric motor and differential. Again, the drive shaft to the wheels would need to be modified, But it was just a little too tall to fit.

While investigating these options, I viewed YouTube videos on Toyota Prius repairs by 'WeberAuto' (John Kelly). Also, see their web page http://www.weber.edu/evtraining

Used motors from wrecked EVs are too big. I looked at buying a new motor. Most are too powerful for a small car or too small, suitable only for golf carts, etc.

Original Imp Motor Specifications

See ImpLeaflets.html for more details.

4 Cylinder 875cc (cm3)

42HP @ 5000rpm (31.3kW)

52lb.ft @2800rpm (70.5N.m)

Car weight: 13.5cwt ( 686kg)


The HPEVS AC-51 or the Motenergy ME1616 appeared to be about the right size for the Imp. I purchased the Motenergy ME1616 motor.


Motor Specifications

Electric Motor: Motenergy ME1616

Brush-less 3 phase Permanent magnet motor

Liquid-cooled, closed frame, sealed motor to IP65 (Note 1)

Operating at 24 to 100 V DC

250A Continuous, 550A (1min)

6000rpm max.

Weight 25.2kg

From the performance graph supplied with the motor.

Power: About 32kW at 5000rpm

Torque: About 75M.m from 0 to 4500rpm, falling to 62N.m at 5000rpm.


Note 1: IP65 is a water resistance rating that means a product is protected against water jets from any direction, but it's not fully waterproof. It can be used outside in the rain.


The electric motor will be in place of the original Imp motor, and they will use the original clutch and gearbox.





EV01 (97K)

The electric motor is on a Homemade gearbox jack used for clutch replacement/repairs. Things are done differently with the Hillman Imp.

EV2 (34K)

The coil and the generator regulator are still to be removed.

More details soon

Ring gear removed from flywheel

Hub made to mount flywheel onto electric motor

Fix flywheel to motor

Keyway cut and flywheel lightened

plate made for electric motor, plte made for gearbox