Go to content Go to navigation Go to search


Read all FAQs...

I want to know if my car [insert any ol’ car here] is a good candidate for conversion to electric power.

Much of it depends on what you want out of the vehicle (performance, range, seating, coolness factor) and how much money you want to invest. Check out this article for some ideas and guidelines: Choosing a Vehicle.

Remember, putting an electric motor and batteries into your car doesn’t necessarily make it a better or more efficient vehicle. If you convert a heavy, gas guzzling car to electric it will most likely be a heavy, electricity guzzling EV.

Comments 27
  1. Michael Liolios    Apr 11, 2007 08:53 AM    #

    I want to know if my car [Nissan Sunny 1985] is a good candidate for conversion to electric power.

  2. — Dan P.    Apr 11, 2007 13:03 PM    #

    In the US, the later models were known as the Nissan Sentra; in Mexico, the Sunny is known as the Nissan Tsuru.
    Yes: http://www.electroauto.com/gallery/sentra.shtml

  3. Gavin Shoebridge    Apr 11, 2007 19:49 PM    #

    Michael, your 85 Sunny would be very similar to my car in size and shape.
    Like my Tredia, it’s smaller than Jerry’s original conversion project of a Mazda 626/Ford Telstar (or whatever it’s known as in the USA!) but you can still fit a suitcase in it.
    As long as it’s a manual (or “stick shift”) you should have no problems…
    Well, none other than the usual!
    Depending on where you’re located, you might have the same problems as myself and Nick Smith (who posts here often). We both have to get all our EV parts from the other side of the world.

  4. — James May    Apr 12, 2007 08:22 AM    #

    I had an ‘85 sunny until ‘03. Unfortunately the head gasket blew so I scrapped it. It was the best (ICE) car I ever had, very efficient, dead light, and has quite a lot of boot room. I think it would be good, it’s certainly a good petrol car, and that’s always a good starting point. You might need uprated springs to take the weight of batteries.

    It’s a similar sort of car to Jerry’s first conversion, I think.

    There’s no power steering, that’s an advantage too.

    Watch for rust.

  5. — Scott Mais    Apr 14, 2007 07:56 AM    #

    I have a question to why an automatic transmission doesn’t make for a good EV conversion car. I have a 2003 Pt cruiser that I’d like to convert, but has an automatic transmission

  6. jerry Halstead    Apr 14, 2007 09:34 AM    #

    Scroll down a couple more FAQs, Scott.

  7. — steve matylewicz    Apr 21, 2007 01:39 AM    #

    I want to know if my car 91 Honda Civic is a good candidate for conversion to electric power.

  8. — James May    Apr 21, 2007 09:25 AM    #

    Hi Steve

    Check out the Hondas on ev album. They might give you an idea of what to aim for.

  9. Gavin Shoebridge    Apr 21, 2007 20:26 PM    #

    I thought about using a 90’s model Honda for my conversion but changed my mind due to the low bonnet height.
    You might find the batteries & controller hit the roof of the bonnet unless done carefully.

  10. — James May    Apr 22, 2007 15:43 PM    #

    That’s what they invented power bulges for!

  11. — Charles    Apr 24, 2007 09:50 AM    #

    I recently procured (aka ripped out of a washing machine by the dumpster outside my building) a 9.7A 120V AC motor (.5HP).
    I dont really know much about it and it comes equipped with a wierd wiring plug that i dont really understand (there are like 10 wires going into the motor) but i was wondering if it would be possible to use a power inverter hooked to a deep cycle battery to run it. (maybe 2 batteries)
    I would be using it on a bike, either mounted on the bike or on a pusher. (probably on a pusher first then upgrade to mounted.)

    Is this overkill? underkill?

    Can you use the general x10 rule in this case giving me about 5hp or is this different for AC?

    Do I need just a regular power inverter or a pure sine wave inverter?

  12. — Charles    Apr 25, 2007 12:04 PM    #

    I was also wondering if i would be able to use a 1200 W dimmer switch as the speed control…
    they are actually pwm … right?

  13. — James May    Apr 25, 2007 13:24 PM    #

    Hi Charles,

    I think you’re going to need to find the schematic for the donor washing machine to find out what all those wires are for. Maybe a single direction single speed tumble dryer motor would be easier to work with!
    I believe dimmer switches are PWM. You might destroy your dimmer switch with transient spikes from your motor, They aren’t designed for that.

  14. — Charles    May 01, 2007 23:11 PM    #

    Is there any way to dampen those spikes??

    Also i found a similar
    motor wiring diagram so i think i should be able to figure out what is what. I do need to bone up on my capacitor start, and what that means and how it works.

    here is my actual motor

    Do you think it would be acceptable to run a bike with just the two given speeds available?

  15. — Dan P.    May 02, 2007 05:32 AM    #


    Item # 1195967 from your link shows a 1” square grid with a lovejoy connector for the motor to be coupled to the washers transmission which makes me think that the motors shaft is approximately ½ of an inch thick and could be to small for any real torque without the aid of a transmission.

  16. — Charles    May 02, 2007 10:58 AM    #

    I guess i didnt really outline my goals…
    it would be a small bike
    (pedal bike not motor bike)
    and i would use a sprocket and chain drive
    I havent worked out the details about this yet, but this will be the easy part of the project.
    maybe no one answered because no one knows, but can you multiply your hp by 10 like with a DC?

  17. — Dan P.    May 03, 2007 03:36 AM    #


    horsepower (hp) convert
    An old unit of power originating from power exerted by a horse. The horsepower was defined by James Watt (1736-1819) who determined that a horse is typically capable of a power rate of 550 foot-pounds per second. Today the SI unit of power is named for Watt, and one horsepower is equal to approximately 746 watts. (Slightly different values have been used in certain industries.)

  18. — Dan P.    May 03, 2007 04:18 AM    #

    You can read more at this link that has a unit conversion calculator at the bottom.

  19. — Charles    May 04, 2007 12:19 PM    #

    HP from an electric motor is computed much differently than that of an internal combustion engine. Therefore it can be difficult to compare hp ratings between an electric motor and an internal combustion. for dc motors there is a rough way to estimate this equivalence, and it is done by multiplying the electric hp by 8-10 times. I want to know if this works for ac motors as well.

  20. Gavin Shoebridge    May 05, 2007 01:18 AM    #

    The main reason for the difference in output power from a motor vs an engine is torque, right?

  21. — Dan P.    May 07, 2007 03:14 AM    #

    Charles, the quick answer is yes and no.

    Whether they are A/C or D/C, they are both Electric motors and deliver their torque differently then an “ICE” Internal Combustion Engine does. The gas engines rating is calculated on its max output but isn’t expected to be operated at that peak for extended periods were as the electric motor can deliver a constant amount of effort in proportion too its voltage and the amperage that it is rated for.

    What you are trying to establish is some “Rule of Thumb” guesstimate to confirm your belief of an electric motor having ten times the horse power then a gas engine; some have much more and others have extremely less,

    To use a 10hp electric motor to perform the same task that a 100hp gas engine does would not be the same as using ¼ hp electric motor to replace a 2.5 hp Briggs & Stratton lawnmower engine.

  22. — Charles    May 07, 2007 10:56 AM    #

    Is the conversion better or worse for a smaller motor?

    Im not really that concerned with performance, I just want a little assurance that Im not going to invest a couple hundred dollars in the project and wind up with a bike that wont go or one that goes 3 miles an hour. Can someone assure me that given the right gear ratio(s) this thing would go 10-15mph?

    Also regarding “transient spikes” The current rating on my motor cant be a continuous rating can it? it has to be peak, right? so i guess im still confused why a dimmer rated over that current would burn out…

  23. — Dan P.    May 07, 2007 14:18 PM    #

    Here is a link to a cool looking home made electric bicycle conversion.
    You might want to email him for some of your questions.

    If you are going to use the A/C motor then you will need an inverter that can produce the required wattage for your motor continuously and a battery with enough amps to maintain that inverter for the desired ride time which is usually 25% DOD before the inverter shuts down. http://www.walmart.com/catalog/product.do?product_id=4891078

    You might eve want to install a small generator or alternator too replenish your batteries while ridding; you could use peddle gearing for comfort against the drag from the alternator / generator setup but you will still need to have the right ratio to emulate an idling engine.

    Though at that point it would become redundant and even less efficient since you would now be peddling so as to spin an alternator / generator that charges the battery which is being inverted from D/C to supply A/C current to a motor that powers the rear wheel opposed to just keeping it as a regular bicycle that wasn’t carrying all the weight of motor, alternator / generator and inverter along with its hardware.

    If you are going to spend money to build this electric bicycle, why not just get a hub kit?
    Besides I think they may have regenerative braking on these for when you are coasting down hills.

  24. — wade    May 21, 2008 23:00 PM    #

    how do I use the EV calculator for a spitfire? What classifies a non-aerodynamic Vs. aerodynamic car?

  25. — josh    May 31, 2008 18:13 PM    #

    I want to convert an older 80’s 3 series BMW. I’m thinking DC would be better then AC current.? But I plan to make it self charging with the use of a few solars and a generator or alt. ?? I would like to make this a fast car too. For drag racing and long distant driving as well. What motor would you recommend. Or would volts be more important? I want a lot of torque and horse power. I’ve looking at advertisement and getting confused. I don’t want the motor to be too heavy. I’m thinking around 200 lbs max. I read somewhere that a 10 hp motor was equal to a 100 hp engine. Is that true and what about the torque. I want this thing fast.

  26. — charlie    Jun 22, 2008 17:55 PM    #

    For Charles and his dimmer switch.

    The reason that you can’t use the dimmer switch to change the speed of your electric motor is that the dimmer switch uses an SCR to clip off a portion of your AC signal. It uses a capacitor and a resistor to phase shift the sine wave for use as a signal to the input of the SCR providing you with a brightness controlled by pulse width, by adding an inductive load like a motor or any other type of electro magnet, transformer etc. you alter the phase shift and reduce the effectiveness the dimmer(capacitive loads will have similar problems operating with an SCR based dimmer). If you feel like seeing what I’m talking about try using a compact florescent light bulb with your SCR dimmer just know that it(the dimmer) will get hot and burn out after a while.

  27. — Jeremy W    Jun 22, 2008 18:47 PM    #

    I dont know about the dimmer switch thing but as far as speed and torque i know a little bit. If you want a high torque but low top speed then use a sprocket with less than 20 teeth at the engine and use a sprocket with at least 40 teeth at the rear wheel. If you want a high top speed (i used this with an ICE from a chainsaw on an old mountain bike of mine and got a top speed of about 70 or 80) then you need to use a sprocket with at least 70 teeth at the engine and a sprocket with less than 15 teeth at the rear wheel. for more speed use a wheel with a larger outer diameter.