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Discussion Starter #1
Hello!

I'm very new to the world of EV conversions and car mechanics in general. Basically, I've ridden bicycles my whole life while waiting for the day that I could afford a practical planet friendly vehicle.

Well I'm now 30 and tired of waiting, so that's what brings me here.

For a donor car I'm looking at a VW type 3 squareback, with a stock curb weight something close to 2000lbs. It actually already has the engine and tranny removed so I was thinking of trying to implement a rear wheel direct drive system. There are several type 3 conversions in the EValbum, but they have kept their transmissions.

My buddy who's garage I'll be using has done a lot of work on VWs so I'm pretty sure I will have some expert advice when it comes to the mechanical side of things. I'm have an EE background so I can grasp most of the electrical details well.

Ideally, I'd like to have enough juice to go about 60mph over 30 miles flat, and still do 50 on 4% grade, although only for about 6 miles. All that without killing the lifetime of my batteries so I guess a 50% DOD to get the most out of them. Average acceleration from stopped is fine with me. I'm not looking to build a dragster.

My budget is pretty low. I'd like to do the whole thing for less than $10K, and I'm in no rush so I'll take my time to find the best deals and hopefully spend less $$$.

So far I've been thinking about a TransWarp 9 or 11 because Netgain seems to make them with direct drive in mind. Not sure what final gear ratio would be optimum. I've heard around 6:1.

I think a curtis controller would suit my needs, but I really don't know how many amps I'm going to need when I merge on the freeway, or even starting from a red light. Also, been reading about the Zapi H2. Regenerative braking would be awesome even at 20% recovery (might help with the drum brakes on hills) and for some reason its a cheaper controller???

As for batteries definitely going with the lead acid batteries since I'm a total newbie and will probably damage the more sensitive ones. Something like 120V or 144V seems what other people have in similar projects. As for 6, 8, or 12V, I'm not really sure which. 6 should give the longest life, but I will end up using the most weight and space right? I'd like to keep the back passenger seats so I will have both the front and back trunks for batteries.

Well thanks for reading. Any thoughts/advice would be greatly appreciated.
 

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Hey,

First, take everything I say with a grain of salt, as I have no practical experience.

Your goals and thinking resonate with me, as similar ideas have been going around in my mind. My brother came up with a neat idea regarding small, direct drive EVs. His idea should work particularly well with front wheel drive cars (I'm not sure if your donor is FWD or RWD). It should work in a RWD aswell, but would need to be install in the trunck, I guess.

Here is his idea in a nutshell:

1) Take out the motor, transmission and front differential
2) Put the rear differential out of a Honda CRV between the front wheels - install it with the input shaft facing forwards
3) Between the electric motor and the CRV differential install a Borg Warner 1350 or 1354 transfer case (from a Ford Ranger, Explorer, Bronco, etc.) These have input and output shafts that face the same direction, so they act as a U-joint in the drive train.

Now, in your car is a two speed system (with no heavy transmission) made from common and inexpensive parts. You can even use an automatic donor.

The rations break down something like this:

CRV dif.: 4.40:1
Transfer case: 1:1 or 2.48:1

The transfer case has electric shifting, and the CRV dif. has a hydraulic clutch.

Does anyone else have a comment on this?
 

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Im somewhat familiar with type 3's, but my question is this. Why go with direct drive? what advantages did you see to go this way? How are you going to do direct drive? even conceptually? Are you having issues with transmission type connection like most of us aircooled users?

Thank you...
 

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For a donor car I'm looking at a VW type 3 squareback, with a stock curb weight something close to 2000lbs.... I was thinking of trying to implement a rear wheel direct drive system. ...
Ideally, I'd like to have enough juice to go about 60mph over 30 miles flat, and still do 50 on 4% grade, although only for about 6 miles. All that without killing the lifetime of my batteries...
I'd like to do the whole thing for less than $10K,
So far I've been thinking about a TransWarp 9 or 11 because Netgain seems to make them with direct drive in mind. ...Regenerative braking would be awesome even at 20% recovery ...
As for batteries definitely going with the lead acid batteries
go with 120v worth of golf cart FLA batteries. trojan 10x1275 (less range), 15xT875 or us battery us8vgchcx. with 120v you'll get your range up around 50 miles and have plenty peppy performance. curtis 1221c controller (400 amp) will be enough with 8" DC will be fine. With DC there is no easy way to get regen. project materials will be $8k-$9k with all new off the shelf stuff.

whoop, and I think you'll want a transmission. If you have gears for reasonable top end, you'll have really piggy accel from a stop. With reasonable starting gear, you'll top out at about 45mph or over-rev the DC motor.
 

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Discussion Starter #5
Im somewhat familiar with type 3's, but my question is this. Why go with direct drive? what advantages did you see to go this way? How are you going to do direct drive? even conceptually? Are you having issues with transmission type connection like most of us aircooled users?

Thank you...
Hi! Thanks for responding.

The car has no transmission already so I don't have much of a choice unless I want to shell out more money for one. I was planning on directly coupling the motor into the drive train/differential, unless I need a separate gearbox. I know that's not very specific, but I actually don't have the car yet.

So advantages: Save weight, money, and not have to learn stick (hehe you guys will probably hate me for that one).

Since I've really never worked on car engines, let alone a VW, I'm not sure why air cooled affects the transmission, but I guess that could be another prob I would avoid with DD. I've read I'll probably need some extra fans to keep the the motor and controller cool since it is only air cooled.

Disadvantage: Not having proper gears for when I need them. Possibly burning motor by drawing too high amps at low RPMs??? Low top end speed?

whoop, and I think you'll want a transmission. If you have gears for reasonable top end, you'll have really piggy accel from a stop. With reasonable starting gear, you'll top out at about 45mph or over-rev the DC motor.
Heh I assume piggy means slow. Or does that mean it just sucks up a lot of amps? I'd like to be able to get on the freeway. I suppose 50mph is enough, but there is one 4% grade section around here that I don't want to have to slow down on.

So, if I did have direct drive, is there an engine and gear ratio combo (assuming stock type 3 tires) that would let me have average acceleration and be able to take the freeway without causing any smoke? I heard most people just use one gear most of the time anyways. Is that only because they aren't taking the freeway ever?

As for regen, what's so hard about using the Zipa H2 aside from the extra complexity of the wiring? Is it not a very reliable controller?

I really appreciate the feedback guys. :)
 

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Discussion Starter #6
I also wanted to pass this along:

http://www.batterysales.com/downloads/UPS12-270FR.pdf

I might be able to get my hands on some used ones of these for free or close to it. I don't see any info about their cycle lifetime on the datasheet, I suppose because they are meant for UPS apps and so wouldn't need frequent cycling. As far as I know the UPS only had to kick in for about 3 hours once when we had an earthquake, so apart from sitting idle for over a year, they should still be pretty fresh.

Does anyone know if these would even be worth a shot? It seems like they can really put out the amps. What kind of battery monitoring or special charging for AGMs would I need to keep from blowing myself up.
 

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I also wanted to pass this along:

http://www.batterysales.com/downloads/UPS12-270FR.pdf

I might be able to get my hands on some used ones of these for free or close to it.
these have half the amp-hr available with flooded lead like
http://www.trojan-battery.com/Products/T-127512V.aspx so, no the UPS batteries really aren't a great solution unless you are on a very tight budget and willing to sacrifice range.



What kind of battery monitoring or special charging for AGMs would I need to keep from blowing myself up.
AGMs have a different charge curve as they prefer to charge slower (having no venting). They tend to have less range than comparable floodies, but better performance for racing use like auto-x because they have less voltage 'sag' under heavy amp use.
 
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You will want to keep the transaxle. Trust me on this one. The transaxle is not like a front wheel drive vehicle. You can find the transmission for a reasonable price if not for free. Really.

What year is your Squareback? That will also make a difference on which transmission you will need.

Try to find a good GE 9" motor. You will pay far less than with a ADC or Warp. It is an excellent motor.

Get a controller that is at least 120 volts and prefer 144 or 156 volts. Get as high of amps as you can. 400 amps is not enough. The Synkromotive controller should fit the bill you need for a fair price. 156 volts and 600+ amps. It is a well built controller and proving to be an excellent controller.

A 67 Squareback is 2095 lbs unladen
Permissible weight is 3037 lbs
Rear axle permissible weight load is 2072 lbs
Front axle permissible weight load is 1212 lbs

As you can see the VW is light weight and can hold load of batteries. Loads.

Batteries should be at least 8 volt or 6 volt golf cart deep cycle batteries. Flooded batteries are a good choice but need care. Pretty easy to do. I use the 6 volt energizer GC2's from Sams and so far so good.

I am getting my Synkromotive controller tomorrow and will be upgrading to 96 volts as soon as it arrives. My ride has limited space so for now 96 volts is what it will be. I too am looking for an early 67 or earlier Type III Fastback, or Notchback. More room for my size.

Pete :)

http://greenev.zapto.org/electricvw

PS. I think your goal is attainable with your budget of 10K as long as you don't pay 10K for your ride. Damn VW's are getting pricy.
 

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Get a controller that is at least 120 volts and prefer 144 or 156 volts. Get as high of amps as you can. 400 amps is not enough.

aahhhh, what is 'enough'?

400 amps in a 96 volt system is 'plenty'. I hardly ever draw 300 except under full accel from a light or up a steep hill. ;) If you go over 120v, the controllers and chargers get way more expensive. 120v worth of 8v batteries will meet his range and speed goals easily I think.... The curtis 1221c is rated for 120v and 400amps at 120v would be PLENTY for an 8" or 9" I think...
 

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Yes, keep the transaxle. This is a really easy conversion (mechanical-wise) with the stock setup, assuming it is a standard transmission (not automatic). There are various adapters for VW conversions and a Type 3 (Squareback) motor mounts exactly the same as a Type 1 (Bug) so any Beetle-to-electric adapter will work fine. Cooling tin and oil fill stuff on a Type 3 are the only thing that's different from a Type 1 and this doesn't matter in your case anyway. Find a standard trans and hook up the axle shafts (probably still there) and you're good to go. It shouldn't be hard to find a good used trans - your mechanic friend should be able to locate one. Or you can buy a rebuilt one from various suppliers in just about any gear ratio you can imagine.
 
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aahhhh, what is 'enough'?
Enough is a relative term and can be taken many ways. My system could be "enough" but would be pushing the limits and I guarantee you'd want more. A 96 volt system at 400 amps could be enough and better than mine but the amp draw could easily go over 400 amps on acceleration on a hill. Heck I can pull mine into that range on flat ground. Acceleration would be better with 96 volts.

A better "enough" system would be 120 or 144 or 156 volt system at as high of amps as you can get. Reason is that you may want or NEED that extra ooooomph and if you were to ever venture into an area with steeper hills you'd be more able to handle the situation. With a minimal "enough" system you may get stuck at the bottom of a hill.

Granted the extra "enough" system will cost more but will allow you more wiggle room and your performance will be far better.

If you decide to go more than 96 volts then get a controller that will go up to at least 144 volts. Most high voltage controllers do not require you to use the max voltage and you could just use lets say 120 volts with a 144 volt controller and be quite happy and your controller would be happy too.

I'd say for your desired setup you could get away with 96 volts but 120 or up would be better. With your budget you could afford the extra and you would be a happy camper if you did.

Pete :)
 

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Hi! Thanks for responding.

The car has no transmission already so I don't have much of a choice unless I want to shell out more money for one. I was planning on directly coupling the motor into the drive train/differential, unless I need a separate gearbox. I know that's not very specific, but I actually don't have the car yet.:)

Hold on, maybe we are confusing transmission and differential here with aircooled and water cooled. I believe that with aircooled engines such as your type3... differential and transmission is one whole unit and cannot be separated. So if you have a transmission then you have the drive train and differential. If you dont have one then you dont have the other....

I hope I am clear. They are one. Im sure more aircooled experts here will chime in.... And there is a big chance that you have a rolling type 3. This means that you have the a complete car without the engine. And most of the time, the tranmission comes with the pan....

C
 

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So advantages: Save weight, money, and not have to learn stick (hehe you guys will probably hate me for that one).

Since I've really never worked on car engines, let alone a VW, I'm not sure why air cooled affects the transmission, but I guess that could be another prob I would avoid with DD. I've read I'll probably need some extra fans to keep the the motor and controller cool since it is only air cooled.
:)
Believe me, learning the stick shift on an EV is very easy. You can even leave it at 2nd gear if you want. And I dont believe that this will be the only limiting factor of not having the transmission.

C
 
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All the old air cooled VW's have a transaxle. It is a single combo unit of transmission and differential. You MUST use the transaxle. Installing a transaxle is actually pretty easy. Use new bushings.

What year is your Squareback? I can help and so can thesamba. They have loads of information. Don't skimp. With a VW you will use all 4 gears. I guarantee it. You may not use first as much but at freeway speeds you will want to use the transmission. Keep the clutch too.

PM me and I can help.

Pete :)

Been doing VW's since 1974.
 

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Discussion Starter #16
OK I understand now the situation with the transmission and differential being all in one. It is a 1971 Squareback and I hear that I can probably use any VW transaxle (including busses) up to 1979. Plus I have always wanted to get better at stick. Just last year my lame ass failed at being a bachelor party DD because I couldn't handle a manual transmission, and so my best friend took over and got a DUI. :(

So I was looking at the Synkromotive controller. I like the idea of not having the whine sound. Need to read more of the reviews since its new on the market. I still like the idea of the Zipa H2 for the regen and cheapness. Can anyone help me understand why everyone doesn't just use these or the other DC series wound regen capable controllers?

My god there are so many variables to think about here. I'm spending hours playing around with the EV calculator (by the way is there a more up to date one somewhere?). So of the lead acid batteries, do 6V always have the highest peukert capacity? I was hoping to go with 12V to save on space and because I can use the old UPS AGM batteries just to test things out without changing any layout.

Try to find a good GE 9" motor. You will pay far less than with a ADC or Warp. It is an excellent motor.
Where do I find 9" GE motors?

Thanks for the feeback!
 

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So I was looking at the Synkromotive controller. I like the idea of not having the whine sound.
the curtis whine is only at very low draw, then it goes away. Its kind of a safety feature when pulling out of parking spots. ;0

I still like the idea of the Zipa H2 for the regen and cheapness.
anything that sounds too good to be true probably is.... i guess i'd want to hear some testimonials, and see how they hold up! I kinda wonder how much regen you get, and how they prevent backfeeding too many amps and boiling batteries.


I was hoping to go with 12V to save on space and because I can use the old UPS AGM batteries just to test things out without changing any layout.
not a good idea. the 12v UPS AGM batteries would require different charge curve, so you would need to change your charger, or set it, when you change to FLA. Also the UPS batteries are smaller, and a good 12v scrubber battery like trojan 1275 is physically larger so your racking would need to be designed with that in mind. whether you use 8v, 12v, or 6v at a given voltage depends on what the total pack energy is you are trying for to obtain your range.... and how much weight the vehicle can bear. You will have better range at a given voltage with 8v over 12v.


Where do I find 9" GE motors?
I dunno.... The ADC, Warp and Netgains seem to be defacto standard and widely available.
 
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Well in a nut shell folks had little access to good interpole motors and the Zapi H2 was not easy to get your hands on. The H2 is a proven player. The H3 is also a proven player but many tried to use the H3 in too large of vehicle an used full regen and that was just too much feedback for the H3. In a light weight car and partial regen the H3 will survive. The H2 is more robust in that area and can handle considerably more. Since it was hard to get these components others found Curtis and ADC and decided that those were enough and promoted them to the hilt. Many who promote them also sell them. Mmmmmmmm. The Zapi H2 is not a too good to be true controller. Just hard to get and then you need to match it up to a good motor with interpoles. Also the H2 and H3 are not cheap. They are very expensive. I am getting a new quote on the H2's this week. You don't find used ones because they are still being used. They are good.

The Curtis is a proven excellent controller but for Series only and no regen which I agree is not a real big deal. But the Curtis and others are limited in amperage. Ouch. Some are limited in voltage and amperage and some are only low voltage systems period.

The best proven controller on the market is Zilla. Both versions. It is over built and pretty much assures that it will live in most any environment.

Others are breaking into the market to address some of those issues. Synkromotive is for mid to small sized vehicles.

Pete :)

PS. I am still doing research on other controllers on the market.
 
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I say 6 volt because you will have plenty of room to hold the batteries and the car should hold enough of them to give you a good 144 volt pack. Excellent for power and distance as long as you are connected to a good controller. To me 400 amps is just not enough. Granted you rarely every use more than that on a normal drive but to have extra if you need it is a good thing.

The 71 Squareback is not a popular and cheaper to obtain. It requires that you have a motor support bracket. Yes you can use the heftier bus transaxle. You may not need to but you can. The stock one is pretty good. The bus one is more expensive. You have plenty of battery room in that vehicle and do not go with a low voltage system in that vehicle. It is heavier than the Beetle or Ghia and you will need the extra power. Still it is a good vehicle. I will get weights for you on that year Squareback.


Pete :)
 
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71 Squareback

Unladen weight: 2282 lbs
Permissible total weight: 3274 lbs
Permissible load: 992 lbs

With stock suspension components.
 
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