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Hi,

I don't know the exact model yet but I am trying to convert an old Toyota Corolla. And I am on a tight budget of around 2k. The car doesn't have an engine but everything else works fine.

My priority is mileage. And I can work with speeds of less than 45 miles/h. But I live in a hilly region. So it must be able to climb hills.

Because where I live I cannot get parts easily I have limited choices. Right now I am only able to find a refurbished D.C. Motors K91-4003 6.7" motor which the seller has agreed for $500.

I am also looking in aliexpress.com for other options.

Is D.C. Motors K91-4003 6.7" motor a good choice. And what is the mileage I can expect?

This is my first attempt at conversion.
All the best,
 

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you are going to find it challenging to build a functional EV for $2K. You will have to resort to surplus or homebuilt everything, and hopefully you are adept at substituting ingenuity, patience and lots of access to surplus junk for budget. Your best bets are:

1) Get all the bits you can out of a 72V forklift or golf cart. Don't go any lower on voltage. You will probably be able to find workable controller, fuses, contactors, maybe the charger. Anything over 72v starts getting less common, and thus more expensive.
2) Get lucky and find a functional battery big enough to power your car for the needed distance. Best bet is possibly a fractional LEAF pack or chevy volt pack, in either case reconfigured for 72V.
3) some kind of basic BMS (if only, voltmeter on every 12V or so worth of cells; you will only need 6, cheap on ebay)
4) DIY charger or some kind of charger(s) configuration such as multi bank chargers designed for RVs or boats. (but these are typically meant for lead acid, might under or overcharge lithium)

Another possibility is to find and buy an abandoned or unfinished conversion. That is often the cheapest way to get components if you know what you are looking for. Just get one that is halfway modern and not weathered to uselessness. Just don't expect to get good batteries that way.

The good news is a small old corolla is light and simple. You will want to strip out every last pound you don't need owing to the small motor. From that standpoint, Its a good place to start. A 6.7" motor will be enough even with hills if you keep the transmission and don't expect top speeds much past 40-45mph, and hill climbing slower than that. At lower speeds it will be capable of, if the car rolls well you might be able to achieve 150-200wh/mile so an 8kwh battery (6kwh usable, half a volt pack) would still give 30 miles or so of range.

You would be much better off if you could bump that budget up to at least $5K though.

Good luck.
 

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Hi,

I don't know the exact model yet but I am trying to convert an old Toyota Corolla. And I am on a tight budget of around 2k. The car doesn't have an engine but everything else works fine.

My priority is mileage. And I can work with speeds of less than 45 miles/h. But I live in a hilly region. So it must be able to climb hills.

Because where I live I cannot get parts easily I have limited choices. Right now I am only able to find a refurbished D.C. Motors K91-4003 6.7" motor which the seller has agreed for $500.

I am also looking in aliexpress.com for other options.

Is D.C. Motors K91-4003 6.7" motor a good choice. And what is the mileage I can expect?

This is my first attempt at conversion.
All the best,

you are going to find it challenging to build a functional EV for $2K. You will have to resort to surplus or homebuilt everything, and hopefully you are adept at substituting ingenuity, patience and lots of access to surplus junk for budget. Your best bets are:

1) Get all the bits you can out of a 72V forklift or golf cart. Don't go any lower on voltage. You will probably be able to find workable controller, fuses, contactors, maybe the charger. Anything over 72v starts getting less common, and thus more expensive.
2) Get lucky and find a functional battery big enough to power your car for the needed distance. Best bet is possibly a fractional LEAF pack or chevy volt pack, in either case reconfigured for 72V.
3) some kind of basic BMS (if only, voltmeter on every 12V or so worth of cells; you will only need 6, cheap on ebay)
4) DIY charger or some kind of charger(s) configuration such as multi bank chargers designed for RVs or boats. (but these are typically meant for lead acid, might under or overcharge lithium)

Another possibility is to find and buy an abandoned or unfinished conversion. That is often the cheapest way to get components if you know what you are looking for. Just get one that is halfway modern and not weathered to uselessness. Just don't expect to get good batteries that way.

The good news is a small old corolla is light and simple. You will want to strip out every last pound you don't need owing to the small motor. From that standpoint, Its a good place to start. A 6.7" motor will be enough even with hills if you keep the transmission and don't expect top speeds much past 40-45mph, and hill climbing slower than that. At lower speeds it will be capable of, if the car rolls well you might be able to achieve 150-200wh/mile so an 8kwh battery (6kwh usable, half a volt pack) would still give 30 miles or so of range.

You would be much better off if you could bump that budget up to at least $5K though.

Good luck.
$5,000 is a little more realistic for a reliable conversion but I think the 6inch motor is going to be a disappointment.
 
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