1986 MR2 EV Conversion NotesKen Chiang

My “Tesla Roadster” Requirements

Get me to and from work 5 days a week, 50 miles a day.

Hilly Terrain 9% Grade hill for ½ mile at end of my commute.

Fast Charge: for example, not 12 hours Safe

The main components ICE Components removed Replaced by:

Radiator system -----> n/a Engine ----------> motor Fuel Tank ----------> batteries & charger Alternator --------> DC/DC converter Starter ------> n/a ECU ----------> controller

**The hardest part was figuring out how to fit the battery racks in the small space

Major costs 180AH 144V LiFePO4.................................$11,000 Motor.............................................................$1550 Controller......................................................$1500 Charger* ….....................................................$2500 Cables,contactors,DC-DC,instrumentation...$1000 Adapter plate..................................................$825 Aluminum racks (materials & welding)........$800 Misc Tools.....................................................$500 New suspension/wheel bearings....................$1000 Other …......................................................$5000

Project Resources (1)

Internet! Evalbum.com: met Steve McDonald Electric-cars-are-for-girls.com

Electric Auto Association! Books:

Haynes Manual for 1986 MR2 Convert it: Mike Brown Build your own electric vehicle: Bob Brandt

Project Resources (2)

Friends that I've met after I started: Steve McDonald: 1987 Honda Civic (lead acid) Honn Chhim: 1987 Honda Civic (LiFePO4) Michael Brooks: 1990 Honda CRX (lead acid) Kevin Philips: Aluminum Welder (owns fab shop

in Hayward- great work and very reasonable rates) 510-459-8427

Project Resources (2)

Friends that I've met after I started: Steve McDonald: 1987 Honda Civic (lead acid) Honn Chhim: 1987 Honda Civic (LiFePO4) Michael Brooks: 1990 Honda CRX (lead acid) Kevin Philips: Aluminum Welder (owns fab shop

in Hayward- great work and very reasonable rates) 510-459-8427

Project Resources (3)

Suppliers that I've used EV america in NH: sells kits, offers clutchless

design KTA services: adapter plate for a clutch system. Manzanita Micro: nice PFC Battery charger and

LiFePO4 distributor CleanAutoLLC: EV display 2 (highly

recommended) Alco Metal: cheaper AL than Home depot Naylor steel: anything steel PickNPull: salvage yard for finding misc car parts.

Good Decisions

LiFePO4 vs. wet lead acids Longer range Cheaper per year Better performance Less maintenance and mess

Aluminum racks Saved 150 lbs

Coulomb counting fuel gauge vs. voltage based EV display 2 has a lot of useful features and

accurately tells me how much “fuel” left.

What would I do differently?

Convert a 4 seater New baby boy! Can't fit my entire family in my MR2. :(

Start with something with a better body and power doors and locks instead of adding on afterwards.

Other learnings Check NEMA connectors monthly!

Other learnings Pay special attention to the bolts on the drive train!

CV joint coming lose can cause a lot of damage!

Learnings (cont...) Design system within specs of each component:

LiFePO4 rated at 4C 4*180=720amp draw max ADC 8” motor is rated up to 120V, don't run

144V! LiFePO4 must be banded to prevent expansion during

charge and discharge cycles LiFePO4 should not be oriented flat with terminal on side

(per manufacturer) Can't get white carpool sticker anymore? (tried 3 times) Manzanita PFC chargers not isolated, don't touch terminal

while charging!

How does my “Tesla Roadster” compare?

MR2 ZEV 0 to 60: 10.8s Range: 70-90miles Max Speed: 90mph Cost: $25k New Friends: > 30 Proud Factor: 10 Knowledge Gained: 10

Tesla Roadster 0 to 60: 3.7s Range: 220-300 miles Max Speed: 125mph Cost: $100k New Friends: ? Proud Factor: 10 Knowledge Gained: 5?

Loving the Drive! Almost 12,000 miles == $1400 savings in gas Solar panel payback: 22 years to 8 years.

http:// www.mr2ev.com Places that I've been in my EV from my home in CV

SFO 54 miles Livemore 48 miles San Jose 66 miles San Rafael 76 miles (charged at parking garage)

Planning farther trips by utilizing J1772 adapter for public charging for free! (until 2013)

Maintenance Checklist

Check Tire pressure Monthly

Check high current connections Monthly

Measure top/low voltages Monthly

Check NEMA connectors Monthly

Check all bolts (racks/cv shaft,etc) every 6 months

Rotate Tires every 6 months

Check Brakes every 6 months

Top off transmission fluid? every 6 months

Check motor brushes every 1 year

Feel free to contact me!

Ken Chiang

kchiangusa at gmail dot com

http://www.mr2ev.com

Other cool project from our EAA

Other Cool Projects from our EAA