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Discussion Starter #1 (Edited)
Hello!
I am making this post as a sort of reality check.
I am VERY NEW to the idea of converting my car...

I am thinking of converting my 1988 Jeep Wrangler to an EV (either all electric or hybrid... I don't know yet).
My skills as a mechanic are somewhat limited, but I have a lot of Jeepster friends that might help me out...

My current specs:
-car weighs approx. 4,000 lbs
-automatic transmission
-4x4 capable

My ideal conversion:
-less than $3,000 to complete
-maintain 4x4 capability
-range of at least 85 miles
-maxes out at 75 mph (min), and can maintain that speed for 2+ hrs; will usually be driven at 45 mph though
-charges enough to go about 20 miles within an hour and a half or less
-fully charges in 10 hours or less

I am mostly wondering:
A.) if this is reasonable
B.) given my specs, where my price will likely end up
C.) what my next step ought to be

Thanks so much!!!
 

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You can buy a wrecked Nissan Leaf for $5k and figure out how to adapt the motor to the bellhousing (would require machining work, or a few adapters for almost $1000). You would also need a lot of components from the Leaf to keep the computers happy. It seems like you might lose your back seat to batteries. This would net you something approaching 100mi range, similar power to the 258 motor, and you would need to keep a transmission (though automatics can be tricky). It would be a lot of research and a lot of work. I'm attempting to put a Leaf in a Mini and I'm hoping to be done this year.

Another option is to skimp on batteries, grab a used Warp 9 motor, controller, transmission adapter, and some other bits...It would be easier to adapt the "standard" components rather than the proprietary Leaf stuff, but you would be down on power and range...by like more than half of the Leaf stuff.

This person did one (and there are others as well): https://www.youtube.com/watch?v=0LIMkmX7Kp0

You might also find my early Bronco ruminations relevant: https://www.diyelectriccar.com/forums/showthread.php/planning-early-bronco-conversion-199747.html
 

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Discussion Starter #3
You can buy a wrecked Nissan Leaf for $5k and figure out how to adapt the motor to the bellhousing (would require machining work, or a few adapters for almost $1000). You would also need a lot of components from the Leaf to keep the computers happy. It seems like you might lose your back seat to batteries. This would net you something approaching 100mi range, similar power to the 258 motor, and you would need to keep a transmission (though automatics can be tricky). It would be a lot of research and a lot of work. I'm attempting to put a Leaf in a Mini and I'm hoping to be done this year.

Another option is to skimp on batteries, grab a used Warp 9 motor, controller, transmission adapter, and some other bits...It would be easier to adapt the "standard" components rather than the proprietary Leaf stuff, but you would be down on power and range...by like more than half of the Leaf stuff.

This person did one (and there are others as well): https://www.youtube.com/watch?v=0LIMkmX7Kp0

You might also find my early Bronco ruminations relevant: https://www.diyelectriccar.com/forums/showthread.php/planning-early-bronco-conversion-199747.html
Thank you so much for the advice!
Buying a whole leaf seems a little out of my price range, and I'm not really keen on replacing more of my Jeep than I *Have To* but that does seem like sound advice.
I think I'll look into that Warp 9 thing... Do you think it would be possible to use these more generic components with a Leaf battery? And would that improve my range?
Again, thank you SO SO much!!!
 

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I'm pretty new to this, and this is an oversimplification, but to some degree batteries are batteries. Buying used Leaf batteries is about as good as it gets in terms of bang for buck, and you can wire them up in a bunch of configurations to match the needs of the motor and desired range.

The Leaf battery pack is a 650 lb sled that comes apart into individual modules the size of a notebook. The configuration of the modules—the way they're wired up—determines the total voltage. Changing whether the individual modules are wired in series or in parallel changes the total voltage and current.

You can either buy individual modules and wire them up, or you can buy the whole leaf pack for about $3-4k, take it apart, wire them as you want, and then sell off the rest.

https://pushevs.com/2018/01/29/2018-nissan-leaf-battery-real-specs/

The next question would be "How many do I need?" and I don't know. It depends on the motor, how far you want to go, what you're willing to spend, and how much space you have in the car...
 

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Discussion Starter #5
I'm pretty new to this, and this is an oversimplification, but to some degree batteries are batteries. Buying used Leaf batteries is about as good as it gets in terms of bang for buck, and you can wire them up in a bunch of configurations to match the needs of the motor and desired range.

The Leaf battery pack is a 650 lb sled that comes apart into individual modules the size of a notebook. The configuration of the modules—the way they're wired up—determines the total voltage. Changing whether the individual modules are wired in series or in parallel changes the total voltage and current.

You can either buy individual modules and wire them up, or you can buy the whole leaf pack for about $3-4k, take it apart, wire them as you want, and then sell off the rest.

https://pushevs.com/2018/01/29/2018-nissan-leaf-battery-real-specs/

The next question would be "How many do I need?" and I don't know. It depends on the motor, how far you want to go, what you're willing to spend, and how much space you have in the car...
hmmm... That's really interesting!
It's becoming pretty clear that I have a lot more research to do...
but, that will give me time to save some money for the conversion, I guess!
 

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Do not buy a Warp9.

I don't think anyone buys those anymore.

If you want to go with a DC motor that size, buy a forklift motor from a forklift repair yard (usually garbage to them) for around $200 in scrap. It will perform the same as the Warp9.

Takes you about an hour to get it out your first time, if they let you. Else they probably have one on the shelf that's suitable.

Build a controller yourself and you might get away with $500.

You'll need a vaccuum pump for the brakes.

Batteries will take up the rest.

A little extra for incidentals, wiring, breaker, etc.

$3000 is ambitious but doable if you pinch your pennies.
 

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Discussion Starter #7
Do not buy a Warp9.

I don't think anyone buys those anymore.

If you want to go with a DC motor that size, buy a forklift motor from a forklift repair yard (usually garbage to them) for around $200 in scrap. It will perform the same as the Warp9.

Takes you about an hour to get it out your first time, if they let you. Else they probably have one on the shelf that's suitable.

Build a controller yourself and you might get away with $500.

You'll need a vaccuum pump for the brakes.

Batteries will take up the rest.

A little extra for incidentals, wiring, breaker, etc.

$3000 is ambitious but doable if you pinch your pennies.
Thank you so much for this reply!
I have heard mixed reviews of the Warp 9, so your insight is really appreciated. I'm going to investigate the top speed/torque(?) associated with a forklift motor, as this vehicle is my primary commuter and 4x4 off roader.
you advice is really appreciated, thank you!
 

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I have heard mixed reviews of the Warp 9, so your insight is really appreciated. I'm going to investigate the top speed/torque(?) associated with a forklift motor...
The "WarP" (and ImPulse, and TransWarP) motors from Netgain (and the same thing previously from Advanced DC or "ADC") are all essentially the same as a traditional "forklift" motor - they are series-wound brushed DC motors. They are run slowly at something like 36 to 48 volts in a forklift, and at much higher voltage and speed in an electric car, but the design and basic construction are not any different.

The number on the end of a model name (such as the "9" of "WarP 9") is just the approximate diameter of the motor in inches. Between models of NetGain motors there are small differences in details of the internal construction, and differences in the case and shaft which matter to how they can be mounted and connected to the transmission or driveshaft of the car.

By the way, forklifts are not generally built with these "forklift" motors any more; they now get AC motors. The source of "forklift" motors is old forklift trucks which have been scrapped, and there is no further use for their motors... that's why they're cheap.
 

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My current specs:
-car weighs approx. 4,000 lbs
-automatic transmission
-4x4 capable
Conventional automatic transmissions are unsuitable for use with an electric motor. Some people convert some specific models of long-obsolete automatic transmissions (usually the GM Powerglide from over 50 years ago), but this is really only for drag racing and a properly converted Powerglide costs as much as your whole budget.

If you use a transmission (and you'll probably need to if you go with a "forklift" motor), the straightforward approach would be to replaced the automatic with a (used of course) manual transmission; an old four-speed or even three-speed is fine, no need to for a modern transmission.
 

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Discussion Starter #10 (Edited)
Conventional automatic transmissions are unsuitable for use with an electric motor. Some people convert some specific models of long-obsolete automatic transmissions (usually the GM Powerglide from over 50 years ago), but this is really only for drag racing and a properly converted Powerglide costs as much as your whole budget.

If you use a transmission (and you'll probably need to if you go with a "forklift" motor), the straightforward approach would be to replaced the automatic with a (used of course) manual transmission; an old four-speed or even three-speed is fine, no need to for a modern transmission.
Thank you for your help!

This idea of "if" I use a transmission is kind of new to me...
Are you saying a transmission is optional? and if so, how should I connect the motor to the rest of the car? I'm told that the motor is best connected to the rest of the car via the transmission. Also, if I use a manual, do I have to learn to drive stick? lol

Thanks again!!!
 

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Also, if I use a manual, do I have to learn to drive stick?
Yes, but it is far more forgiving in an EV. You can usually just put it in 2nd or 3rd and go.

If you read that Bronco link, a lot of this is discussed, 'cause I also didn't understand much about electric motors and gearing.
 

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Driving a manual is really pretty easy, and it's easier in an EV. If you're hesitant, I'm sure you'd surprise yourself. Additionally, a manual transmission is a better match for an EV than an automatic. Most EVs just use a single speed gearbox or leave the manual transmission in a single gear 90% of the time.

All that being said, your budget is very tight. I think it would be a huge struggle to build the Jeep for $3,000 while meeting your requirements. Getting lucky with an auction purchase for 90% of the components would be a big win.

I would avoid an old-school DC conversion with a forklift motor. AC motors from production EVs are plentiful and very good, now. The aforementioned lucky auction would get you one that could likely be used, in addition to a large battery pack and a lot of incidentals.
 

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This idea of "if" I use a transmission is kind of new to me...
Are you saying a transmission is optional? and if so, how should I connect the motor to the rest of the car? I'm told that the motor is best connected to the rest of the car via the transmission. Also, if I use a manual, do I have to learn to drive stick?
Yes, but it is far more forgiving in an EV. You can usually just put it in 2nd or 3rd and go.
Additionally, a manual transmission is a better match for an EV than an automatic. Most EVs just use a single speed gearbox or leave the manual transmission in a single gear 90% of the time.
There are two aspects to this:
  1. One purpose of the clutch with a manual transmission (and the torque converter in an automatic) is to slip so the engine can keep running when the car is stopped or moving to slowly... and an electric motor doesn't need this at all.
  2. The whole point of a transmission with more than one gear ratio (or "speed") is to allow the engine speed to stay in a narrow range, but an electric motor can work over a wider speed range, so fewer different ratios are required. With a motor that can handle enough voltage (higher voltages allow higher motor speed) and can produce enough torque at low speed, it works well enough over the whole range of driving speed that only one ratio is needed... and often only two ratios is enough even for cheap motors.

The transmission is the thing between the motor and rest of the car, and aside from the clutch feature and multiple gear ratios, it serves one critical purpose: it adapts the speed of the motor to the speed of the rest of the powertrain. Since motors need to run reasonably fast to produce adequate power, and the wheels of the vehicle turn much more slowly than that, a reduction gearbox is needed. In the case of the Jeep the axles have reduction gears in them, but if that is not a sufficient ratio (and it probably isn't) another gearbox is still needed. This is why many inexpensive conversions keep the transmission, even if it is rarely shifted between gears.

Driving a manual is really pretty easy, and it's easier in an EV. If you're hesitant, I'm sure you'd surprise yourself.
This is true for an EV because you don't need to slip the clutch to start from a standstill at all (the hardest part of driving a manual for many people), and because you don't need to shift very often.

Even in a regular car with an engine, people routinely learn to drive a manual transmission adequately on the first day that they drive, sometimes with no instruction. My wife got about five minutes of instruction from the sales rep at the dealership where she bought her first manual car My parents' last manual transmission car was gone before I arrived, so I learned to drive entirely on automatics. One day at a summer job my boss told me to go get the pickup truck and bring it over to where we were working. I pointed out that I had never driven a manual and he said something like "you know how it works? figure it out", and I did that, since I did understand the basic "push clutch pedal in before moving shift lever" from watching TV. It also had a trailer attached, which I had to back into the desired location, and of course I hadn't towed a trailer, either - that was more of a challenge.

I would avoid an old-school DC conversion with a forklift motor. AC motors from production EVs are plentiful and very good, now. The aforementioned lucky auction would get you one that could likely be used, in addition to a large battery pack and a lot of incidentals.
Skipping over the technical details, modern AC motors are designed to handle high speed and voltage, allowing all production EVs to use single-speed transmissions. With no clutch and only one speed (ratio), they're not really automatic or manual... the driver just doesn't have to do anything. The problems are that:
  • this type of motor with the corresponding controller and high-voltage battery is relatively expensive, unless you are salvaging used parts,
  • it is not easy to work with the control system for a motor from a production car when it is not in the production car, and
  • if you need to use your vehicle's original axles and other drive gear (such as the transfer case), you need to adapt the motor to mount on and connect its output shaft to the other parts (which can be challenging).
 

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Hi Jessica,

I haven't read the entire thread, but I just wanted to say it is possible to convert a Jeep and for it to be a better vehicle than it started out. I am converting my 2003 Jeep Cherokee (Liberty in the US).

My only advice is to do lots of thinking before you pull the trigger so you limit your surprises.

I ended up buying a written-off leaf for the battery which is by far the most expensive part.

Good luck.

http://babyjeep.ferrara.com.au
 

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Jessica,
Strange as it may seem, the DC motors as in forklifts do not have a voltage. The higher the voltage, the lower the amperage has to be. And the higher max speed the motor gets. The higher the voltage you determine you want to use, the more battery cells you will need to provide the voltage thus the cost goes up. Also the controller will have a maximum voltage. I don’t think the jeep will be a real good candidate for electrification. It is too heavy, has way too much rolling resistance. You’re positively must use a manual transmission. Making the automatic work for you would be a huge project. If you want power brakes, then you’re going to have to find a vacuum pump.You will have to decide if you are going to use the clutch or go clutchless.

A most important purchase will be what battery charger you’re going to use. Then you need to purchase batteries, and figure out how to mount them securely in the vehicle. The batteries have to be connected to a controller and the controller connected to the motor. You need an adapter plate to Connect the motor to the Bell housing, and a connection from the electric motor driveshaft to your clutch or transmission. Also purchase a couple contactors to control the electric flow.

The range and speed you are thinking about are worlds beyond the budget you suggest
 

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Strange as it may seem, the DC motors as in forklifts do not have a voltage.
That's true of all motors. They are rated for a specific power output at a specific voltage and load (which corresponds to a specific current), but can be operated under heavier load and/or at higher speed. That requires more voltage, and there is a voltage limit due to the motor's construction, but the limit is often much higher than the rated voltage.

Motors in forklift trucks and other industrial applications are planned to work hard all day long. When used in a car, they may be worked much harder (more voltage and current) and that works okay as long as it is only for brief periods of acceleration.
 

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Insulation is voltage-limited.
I'm guessing that motor voltage is also limited by the commutator construction (such as segment spacing), but I don't really know.

The advance adjustment in a commutator may not give you enough advance for a particularly high voltage.
To explain this...
The main purpose of higher voltage is usually to allow higher motor speed. To operate at higher speed, the timing of the commutator (which means the position of the brushes on the commutator) is routinely adjusted: the brushes are "advanced" so that they switch between segments (corresponding to rotor winding sections) earlier in the rotation. Unfortunately, the timing is fixed (can't change with speed) and so a compromise must be chosen - advanced timing hurts performance at low speed, and zero advance doesn't work for high speed, so the useful speed range is limited by the compromise setting, no matter how much voltage you have available.

All of this discussion of advance and the commutator applies only to brushed DC motors, such as those from old forklifts. AC motors have an equivalent feature ("field weakening" or phase shift), but it is handled automatically by the controller and is not stuck on one setting.
 

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I'm thinking of the same thing with my 92 YJ. Had looked into the kit on line a few years ago. Will have to do some new research now on the various sources of motors and batteries.
 
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