Freshly washedAfter engine removalBefore engine removalMe.  Obviously.Another angle
OwnerEdward Pilbrow
LocationChristchurch, South Island New Zealand map
Email email image
Vehicle1997 Subaru Legacy GTB Limited
Large high-performance station wagon. The rough white one in the photos was for practice. The nice yellow one is the one I am actually converting.

The text and photos show my progress. I will update this page over the next few years as construction is completed. Last update to this page was 26 Feb 2014.
MotorSiemens 1PV5138WS24 3-Phase AC
Was going to use an EVE motor but have heard bad things about them recently so changed to a barely used second hand motor from HEC who were very helpful suppliers. It's a bit larger than I need (came from a bus apparently) but that just means more fun, right? 90kW continuous, water cooled 20L/min, 650V DC bus, 9000RPM, 113kg, US$3000.
Drivetrain4WD with factory traction control, capable of handling 200kW. Manual.
Controller Tumanako
Having rejected MESDEA and Brusa due to price and quality issues, I am now hoping the open source Tumanako project will progress to a useable point in the next few months. I have purchased 2 Semikron Skiip 613GD123-3DUL IGBT modules (US$700 each) and a Greenstage controller board (US$300).
Batteries230 CPP155-360, 3.60 Volt, Lithium-Ion
Looked at Headway and Lifebatt and dodgy Chinese suppliers flogging off "new" A123 cells AMP20 cells for cheap prices after their bankruptcy. None were good enough. Chose Enerdel cells which come in a 12S2P 15.5AH module and are nearly as good as A123 AMP20 cells for half the cost. The side mounted tabs make the BMS design more difficult. 50kW continuous, 150kW for 10s at 1 minute duty cycle, 160kg, US$10000. 11kWh. The chemistry is lithium ion NMC which somehow stands for lithium Nickel Manganese Cobalt oxide (LiNiMnCoO2).
System Voltage700 Volts
TBD. Probably will split the pack in three and charge off the 230V mains in parallel.
HeaterWill have heater and original climate aircon working.
DC/DC Converter
InstrumentationProbably a screen as there is lots of extra info to be displayed compared to a typical conversion. Probably based on an Android tablet.
Top SpeedTBD
AccelerationExpected 0-100kph (0-60mph) under 7s. I may be able to push more than 150kW into the motor (main limitation is the system voltage and battery peak C rating) for very short periods of acceleration.
Range25 Miles (40 Kilometers)
Estimated in EV mode at 100kph (60mph). In EREV mode estimated range is 500km (300 miles), limited only by the original petrol tank size.
Watt Hours/Mile350 Wh/Mile
Estimated 230Wh/km (~370Wh/mile) on average (A Chevy Volt is 500Wh/mile in "EV mode"). Very hard to predict for such a large power-hungry car. Based on coast-down testing.
Seating Capacity4 adults. I have to drop 1 seating space in order to comply with the manufacturer's GVM weight limits. Car weighs 1500kg before conversion and will likely weigh the GVM (1920kg) after.
Curb Weight4,233 Pounds (1,924 Kilograms)
Estimated after conversion.
TiresOriginal 17 inch.
Conversion Time4 years so far researching and sourcing parts. Will be finished November 2014 in time for the big Evolocity event at Ruapuna, Christchurch, New Zealand.
Conversion CostEstimated US$27000.

Cost so far:
Genset engine US$6720
Batteries US$10000
Motor US$3000
Controller US$1000
Car $5600
Additional FeaturesBattery management system:

Expect to use 6 Maxim MAX11068EVMINIQU PCBs for a custom BMS (monitoring, balancing) controlled by a MSP430 microcontroller. The BMS PCBs cost US$150. Although recent investigation suggests these are no longer easily available. Now looking at Enasolar which are in development and expected to be available in a few weeks time.


Have investigated and ruled out motorbike, outboard motor, and go-kart engines. For the power required, it is very difficult to find something small, low revving, water cooled, and reliable. I settled on a Rotron 294 single cylinder water cooled rotary engine made by Parajet. Am now getting it set up and running. This will be coupled mechanically to the rive train via a sprag (one way) bearing and belt. Engine will be connected to existing petrol tank and exhaust system. Estimated required power is 23kW continuous (Chevy Volt is said to require 25kW at highway speeds and 8kW at city speeds). Rotron delivers 25kW at 6500RPM and has a built in reduction belt drive to about 2000RPM. Unfortunately a premix fuel is required for the current model of Rotron (automatic mixing is coming in 2012) so an automatic oil mixer will be implemented to keep with the no compromise theme. Rotron advise that a non-premix version is due out in 12 months (presumably uses direct oil injection?).


Expect to drive the original pump from a belt connected to the generator, similar to how it was connected in the original design. Electric motor will run constantly.

Power steering:

Am currently testing a Toyota MRS electric pump.

Power brakes and vents:

The mechanical components in the ventilation system (and the power brakes) appear to be powered from a vacuum source. Having rejected the cheap Ford Ebay diaphragm pumps due to noise, am currently investigating the Audi Ebay vane pump option that is popular on many forums. I want it to be silent.

Water cooling:

Substantial water and air cooling will be required for most components in the system. As well as the front radiator and aircon radiator, the original turbo bonnet scoop is likely to be utilised.
My goal is to investigate if it is possible (and maybe it isn't with current technology) to do a home conversion that results in a no compromise EV that can serve as my only vehicle, i.e., not a typical home EV conversion that does for only some of my requirements. To achieve this it must be a medium station wagon (to carry decent loads and gear for holidays), must be 4WD (for skiing trips), must be an EREV (to give it useful range and 5 minute "recharging" when on holiday), must be fast (for safe overtaking and not annoying other road users on the narrow hilly New Zealand roads), and must not be missing any of the typical features of a modern car (aircon, power steering and brakes, heater, 5 seats, roofrack, towbar). Anything less would obviously be a compromise, and therefore a fail. If I succeed in my goal, I feel it will be an important milestone in home conversion progress that can be used as a real counter-example to those who say that home conversions always result in a compromised, small, 2nd car.

As far as I can tell, this will be the first ever home made Extended Range Electric Vehicle (EREV) capable of true sustained highway speeds (130kph, 80mph). As at Nov 2013 there are only a handful of true "gasoline-optional" EREVs (see WebPage for a comprehensive list) with many EREVs having either been discontinued (Fisker Karma, BYD F3DM, Toyota RAV4) or still insist on running their engines at times (Toyota Prius, Chevy Volt, BMW i3). The recently accounced Mitsubishi Outlander PHEV come svery close to my goal but won't be as fast or as cheap or as spacious but will probably carry 5 people. In my design, the genset speed will adjust to charge the batteries as much or little as required depending on whether the user wants to run in battery-depletion mode, battery-sustain mode, or more of a mixed cycle mode. Most importantly, it will be able to be switched off under driver control so this is a proper EREV and not a common plug in hybrid. This will allow all the benefits of a pure EV such as oil-free short trips like commuting to work and back, zero pollution driving when in crowded carparks, and silent driving when in rural towns and when arriving home late at night, without the range limitation. Please contact me if you have any experience or ideas for the genset as this looks to be the most difficult and unique part of the project.

code by jerry