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Discussion Starter · #1 ·
Hello there.


I'm wondering how long the motor can be if I decide to keep the transmission. I'd hate to get a motor that's too big.


The gas 1.8 motor is still in mine. I just got the car and I'm fixing up the interior, and some broken things around the car before I tear the motor out of it.


My plan is to use a 36 or 48v motor whatever I can find that fits at the forklift junkyard with a curtis PWM, some new lead acid bats, a throttle that links to the gas pedal cable. Trying to keep it as simple as possible since this is my first ev conversion.

I haven't researched the breaks on this vehicle too much so I don't know if they are power driven, also the power steering is a question I havn't had answered yet.

If anyone knows anyone who has done one of these vehicles before or a page or guide to someone who has done something on this vehicle that would be so great. So so great. I don't have access to the garage, and I couldn't figure out how to make that work. I'm sorta a forum newbie, and I honestly hate reading. I learn most of my info from other humans, and videos. This has served me very well in the past.


Anyways Thanks for reading!


Joel
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If you ever get an impulse motor, I have an CanEV adapter plate and hub for rabbit. I wouldn't spend the effort on a 36V conversion it will be too slow
 

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Not sure of the size motor that will fit but it won't be a big one. Sounds like you are out for a budget build. If you get a forklift motor get one that has the internal fan and standard motor shaft. The controller should be able to do at least 120 volts and 600 amps if you want any reasonable performance and speeds. The lead acid batteries will get you started but you will soon realize that they are too damn heavy and too much work to keep going for any length of time. Capacity performance will suck too. My first build was a VW Ghia with a 9" GE motor and a 72 volt. 550amp controller. I then got my first Synkromotive controller Beta Unit and jumped up to 96 volts and 800 amps. Big performance boost but my range with new deep cycle golf cart batteries was still no better than 25 miles and at that mileage the performance had dropped so low I was only doing about 25mph. You will be much better off getting your hands on some good used Lithium cells from the start if you can. If you can't jus know you won't be going 60 miles at freeway speed with lead acid batteries in that vehicle.

check this place out for ideas for your build. Just search vw and you can find others who did the same vehicle and you can get an idea of your motor size.

http://www.evalbum.com

I'd say go AC motor if your budget will allow. An AC-35 or 50 would do well in that vehicle.
 

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Discussion Starter · #4 ·
Wow! Great info. Thanks for the heads up. I'd hate to reinvent the wheel only to find out it's actually fire and get burnt.


So here's where I am at now with my questionings.


So what if I remove most of the components, all the components possible, including the cv axles and transmission, and use a 3 phase system with 4 motors and a controller that can recharge the batteries with a contacter between the controller, and the motor that can switch the motors to go in reverse. Is this possible with a 3 phase motor system? Also I was thinking of a switch between the motor and the controller in case the controller burns out I can disconnect all the electricity. What type of controller can do all this? I know it's possible because I can see it in my mind. Maybe recharging the batteries with the 3 phase system might be enough to make it a worth whiles system with lead acid batteries?


Otherwise I think I'm going to scrap the whole project, because I honestly don't have the skrill or willpower to build myself a lithium ion battery pack. Collecting used batteries, testing them, filing them, charging them, checking the loads, and then fabricating a battery pack just seems like it would make the scope of the project way to extreme for my noobie ass.


Unless someone knows of a battery type person who could mentor me in the Portland area, or in someone I could call/text if I have questions. All the battery experts I know of are way to busy/expensive for my scope.


THANKS SO MUCH!!



THIS IS FUCKING AWESOME!


Joel
 

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Discussion Starter · #5 ·
I just realized the rear differential would get in the way of me applying a motor system to the rear. So I guess it would have to be a two motor system for the front only which might not suffice?


Please help!
 

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I honestly don't have the skrill or willpower to build myself a lithium ion battery pack
Maybe, but you can learn a lot by reading here or you can buy a prepared battery like this: https://evbatterycenter.com/HAC4/in...ashop&view=category&layout=listing&Itemid=605
They can include charger and BMS.

A 72V conversion could be safer and easy to build and easy for your budget if you want to learn with a nice project.
https://www.diyelectriccar.com/forums/showthread.php/72v-systems-small-car-68596.html
 

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Power brakes?

I haven't researched the breaks on this vehicle too much so I don't know if they are power driven...
Essentially all vehicles as new as this have power-assisted brakes... including any 1984 Rabbit. The big round device at the base of the brake master cylinder is the vacuum assist booster. There was a diesel available in that generation of Rabbit/Golf, and a diesel doesn't have engine vacuum to run the brakes, so it uses a vacuum pump driven by the engine - but you won't have that pump.

This is a normal situation for an EV conversion, so the solution alternatives will be the same as for any other conversion... but you need something, or the brakes will be very difficult to use.
 

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Power steering?

... also the power steering is a question I havn't had answered yet.
A Rabbit of that vintage might have power-assisted or manual steering. If it has manual steering, nothing needs to be done; if it has power-assisted steering, the easiest solution is to swap in a manual steering rack.
 

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Garage for examples

If anyone knows anyone who has done one of these vehicles before or a page or guide to someone who has done something on this vehicle that would be so great. So so great. I don't have access to the garage, and I couldn't figure out how to make that work.
The DIY Electric Car Garage is not working, and will probably never work again. It is possible to find most of the content from the Wayback Machine, but it's probably not worth the trouble. As already suggested, you could look in EV Album, which is similar, for VW Rabbit/Golf examples.
 

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Drive configuration

My plan is to use a 36 or 48v motor whatever I can find that fits at the forklift junkyard with a curtis PWM, some new lead acid bats, a throttle that links to the gas pedal cable. Trying to keep it as simple as possible since this is my first ev conversion.
Other than using lead-acid batteries, that makes sense as a starter project.

So what if I remove most of the components, all the components possible, including the cv axles and transmission, and use a 3 phase system with 4 motors...
Wow, is that a huge jump! :eek:

This is a bit like going from "I think I'll make a homebuilt small airplane from a kit" to "but maybe I'll build a next-generation Space Shuttle". :D

I just realized the rear differential would get in the way of me applying a motor system to the rear. So I guess it would have to be a two motor system for the front only which might not suffice?
What rear differential? The Rabbit doesn't have one, and if it did (if you were starting with an all-wheel-drive model) it wouldn't be in the way any more than the transaxle is in the way in the front. Perhaps I just don't understand what drive configuration is being proposed...
 

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Lithium battery

... I honestly don't have the skrill or willpower to build myself a lithium ion battery pack. Collecting used batteries, testing them, filing them, charging them, checking the loads, and then fabricating a battery pack just seems like it would make the scope of the project way to extreme for my noobie ass.
Almost nobody actually does that, although many new forum members say that's what they plan to do.

A few years ago the common approach to a lithium battery was to buy new large LiFePO4 cells (such as from CALB), and combine the required number. Nothing used, no testing, no welding connections, and the battery pack is just a bunch of these cells in a box with a cables connecting them... plus usually a Battery Management System of some sort.

It seems that the most common current approach is to buy modules (assembled groups of cells) from the battery pack of a production EV (usually salvaged, sometimes new) and connect enough of them to reach the desired operating voltage. The original BMS can even be used to some extent, depending on the brand and model chosen.
 

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3-phase (AC) control

So what if I remove most of the components, all the components possible, including the cv axles and transmission, and use a 3 phase system with 4 motors and a controller that can recharge the batteries with a contacter between the controller, and the motor that can switch the motors to go in reverse. Is this possible with a 3 phase motor system?
An AC motor controller (they're all 3-phase) doesn't use switches between the controller and motor for reverse - any AC controller does that itself (by driving the phases in the opposite order). This easy way to reverse is one reason that some people choose AC rather than DC, especially if they don't want to use a traditional transmission with a reverse gear.

Also I was thinking of a switch between the motor and the controller in case the controller burns out I can disconnect all the electricity.
That's not needed, and not done; every production EV just has direct cables from the controller output to the motor (and they're often buried in the controller and motor housing so you don't see them). There does need to be a relay (contactor) which can shut off the power from the battery to the controller.
 

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Discussion Starter · #13 ·
Cool. going to read all the literature posted so far, and repost again with my ideas/thoughts. THANKS SO MUCH EVERYONE!!


Also what is BSM?
 

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Maybe, but you can learn a lot by reading here or you can buy a prepared battery like this: https://evbatterycenter.com/HAC4/in...ashop&view=category&layout=listing&Itemid=605
They can include charger and BMS.
... the battery pack is just a bunch of these cells in a box with a cables connecting them... plus usually a Battery Management System of some sort.

It seems that the most common current approach is to buy modules (assembled groups of cells) from the battery pack of a production EV (usually salvaged, sometimes new) and connect enough of them to reach the desired operating voltage. The original BMS can even be used to some extent, depending on the brand and model chosen.
Also what is BSM?
A "BMS" is a Battery Management System. It monitors the voltage of each cell level (not just the battery overall) and may (depending on system) balance the cells (equalize their charges) by discharging cells which are overcharged and/or charging cells which are undercharged. It usually determines the overall State of Charge of the battery, so it can tell the driver how much energy is left, and stop the vehicle from being driven when the battery charge is too low.
 
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