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'69 VW Beetle Electric Grocery Getter on the cheap

125K views 189 replies 30 participants last post by  marklaken 
#1 ·
I recently bought an unfinished vw beetle electric conversion off craigslist and intend to follow through on a basic, short distance, fair weather, in-town, electric car for my wife. It'll be her birthday present which comes up in mid-May, so i got my work cutout for me. I am an air-cooled vw car restoration enthusiast and do all my own welding, mechanical, body, electrical, hydraulics, etc.

My goal is to put together a quality electric Beetle for as little cost as possible. It needs to go 40mph for 25% of the time, 30mph for 75% of the time, and have a range of 20 miles.

I want the vehicle to be stupid simple. For my non-mechanically inclined wife, I would like to just have a single outlet for the charger and a simple driver/car interface. I do not intend to install a voltmeter or amp meter. I would like to install a range indicator (I saw one for around $50 online somewhere).

My value system is as follows and will dictate my system purchases:
Safety > Durability > Simplicity > Range > Speed > Comfort

I am currently thinking of following through with the EV Wilderness setup of a 72 volt Alltrax 450Amp controller powering an ES-15A Series Motor (40HP peak, 12 HP continuous).

I already have the EV Wilderness VW adapter plate and shaft coupler for the ES-15A motor and also the throttle box and Kilovac EV200 Contactor (these parts came with the beetle).

Any other recommendations or thoughts on controller and/or motor?

I could use help sizing the batteries for my requirements. My general thought is either 9 - 8volt golf cart batteries or 12 -6volt golf cart batteries. Any opinions? Would 9 - 8v batteries cut it for my needs (I had read somewhere that 8v batteries need to be replaced more frequently (less charge cycle life). I had also read that a rule of thumb is about 3 miles/battery for in town driving - which I am sure is an oversimplification)

I also am torn between spending the money for a 72v to 12v converter for 12v accessories or maintaining a separate 12v deep cycle battery (came with the car) with a separate 12v charger (I have an old marine battery charger). Basically the converter option costs a couple hundred bucks, but is simpler to operate. Any major disadvantage to the converter? Better to spend my money elsewhere and stick with the second charger and battery which i already own? - Can I wire both chargers to one plug-in location? Does the 12v charger need to be connected/disconnected from the battery every time the 12v battery is charged?

I have not shopped for 72V battery chargers and am open to suggestions.

I am currently cleaning the body and repairing the floorboards. I have also ordered a front disc brake conversion to help stop the heavy beetle. No power steering, power brakes, AC or heat on VWs, so that part is really easy.

I'll post some pictures tomorrow...

Mark
 
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#2 · (Edited)
Everybody here is going to try to convince you to run lithium chemistry batteries, citing all sort of nefarious schemes, but you won't be able to do really dirt cheap. Your conversion. I'm doing lead acid, and I don't care what they think. YMMV. Sounds like you have done some homework, which is a good thing. stick around some more, enjoy the forum, and welcome aboard. I am running 12 v batteries, because I think it suits the Kostov motor more, but the opinion is that if you have the room, the 6 or 8 v batteries are better. I went with an alternator since it was mostly dangling in the engine compartment waiting to be used. Others will chime in with their different thoughts soon and they are all valid for their application. remember YMMV..
 
#15 ·
Everybody here is going to try to convince you to run lithium chemistry batteries, citing all sort of nefarious schemes, but you won't be able to do really dirt cheap.
How refreshing. Yes, lithium makes complete sense but I too am going for lead, cheap lead, for my mk1 car. I will go lithium in the long run and, yes, it will cost more in total but I want to get up and running and I only have a 12 mile commute (in total) so will go big on lead to reduce the C loading on the pack. I am going for lead and, I hope, won't be struck down for it!!!

Good luck with the bug and tell your wife to go easy on the gas pedal and try to drive in such a way that she'll never need to touch the dreaded brake pedal!!! Nice christian driving is what we need!! :eek:
 
#3 ·
Golf cart batteries are my only option at my price point - spend now or spend later, I guess I am in the spend later camp...I hope to do the entire conversion for under $4k. So far I have $750 invested in the car and partial conversion and $250 invested in a disc brake conversion. a quick online window shopping trip puts me around $1300 for motor and controller, $900 to $1200 on batteries, $300 on misc electric parts, and $400 on a charger.
 
#4 ·
I do not intend to install a voltmeter or amp meter. I would like to install a range indicator (I saw one for around $50 online somewhere).

My value system is as follows and will dictate my system purchases:
Safety > Durability > Simplicity > Range > Speed > Comfort
I can't imagine an EV without Volt/amp meters. At least get a Volt meter. They don't have to cost that much, you can get digitals for $5-15.

8v golf cart batteries should work fine, but i don't know if you'll get the speed you need off just 72V.

12v charger should be fine, you can run it along with the pack charger and leave it connected, but check it for leakage. Some drain a little power from the batt when not plugged in.

Disk brake upgrade is great. Is yours the bolt on or spindle replace type?
 
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#6 ·
For your needs. Your needs are really not realistic. In real world driving you will want a vehicle that can do freeway speeds with no problem. You will want to be able to scoot out fast if needed. Not that you must have it but for safety sake you don't want a slug of a car. It leaves a sour impression on people.
I drive every day 12-15 miles round trip for 10 years now. My max speed is 45mph. My car hasn't hit 65 mph since the first week I bought it. What's not realistic? What's not real world about that? Maybe a <65mph car doesn't fit your needs, but for some of us it does...

I'm with ya on the lithiums though... Small (low speed-short range) lithium packs are not that expensive. 50-60ah CALBs or Headways is what I'm looking at, but I'll have a lighter car.
 
#5 ·
I put a couple pictures in an album.

Regarding meters, what advantage do the meters provide over a range meter? Is it for diagnostics?

Thanks for the heads up on the downside of the lead acid battery - is acid spray and venting an issue with a gel based lead battery? The decrease in performance at half charge is especially noteworthy and would push me to 12 - 6v batteries as my minimum criteria.

As far as Lithium, are there good sources for used lithium batteries and what are some of the more affordable charger makes/model. I will have to do some research here...

I know I won't need a 65 mph car, but I would want acceleration to be acceptable for street use (35 mph streets with lots of stoplights). I have old vws and am used to being the slowpoke, but will my general setup be worse than say a split window bus (0-40 mph in about 30 seconds)?
 
#9 ·
Regarding meters, what advantage do the meters provide over a range meter? Is it for diagnostics?

I have old vws and am used to being the slowpoke, but will my general setup be worse than say a split window bus (0-40 mph in about 30 seconds)?
Definitely for diagnostics, but also for driving. What range meter are you looking at? The issue there is that range is a factor of many things, which can be difficult for an electronic device to figure out. With a voltmeter and experience you know what range you have left based on the sag (For lead, for lithium you need to measure in and out).

Being used to a slug you should be fine performance-wise. I don't know your motor specs, but running my 31B on 120V lead I can do 0-40 in ~6 sec.
 
#7 ·
Lead/acid batteries.....Been there-done that-bought the tee shirt, got the tattoo and class ring....

1-Do NOT buy the batteries with the top-threaded posts. They pull out, loosen up in the lead and burn off because they are good for 75 amps max...get the traditional tapered lead post type.

2-They require service every 4-6 weeks. water, cleaning and retorque posts.

Otherwise, they make a great MK-1 vehicle. Your learner. Something to be constantly improved on. {little things}

Yes, most chargers will leak back somewhat when unplugged. Not much, they just do. You can use a charging relay to stop this. Have it turn on when the car is plugged in. Then kick out when unplugged. Simple. Use an AC line voltage motor contactor.

Everyone has a "first" EV. It really changes the way you think about most everything.

Miz
 
#8 ·
Well, lead acid is your choice!
Lithium can cost 2-2.5k$ instead of 1k$ but will weight a third and take half place.
Anyway, you can expect the upgrade to lithium in a year or so if she like the car....

72v can be fine for a low speed conversion, but I suggest to you to go for the new line of SPM Alltrax controller. They have integrated cooling systems and seem better than Axe series for a similar price.

Also, I have a D&D ES-15-A comming from my motorcycle to sold... If you are interested: http://www.diyelectriccar.com/forums/showthread.php?t=56797

Selected the right gear can be important for the proper life of motor because the car will probably be able to start and maintain speed in third gear all the time, but motor will suffer of overheating.
Maintain high rpm (>3000) can be important for small motor for proper cooling.
So how do you think she will drive the car?
 
#10 ·
Thanks for the input everyone. I already know more than I did after about a year of casual internet searching regarding EV conversions. One thing I forgot about was the tax credit for converting a car to electric. Does anyone know when that tax credit phases out (Is it still 10% and is it still good for 2012?) - perhaps that could help me get to lithium ion batteries...

in regards to disc brakes, it is a quick bolt in swap on post '66 beetles which have ball joint front suspension.
 
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#14 ·
Buy one motor that can do 72 volts or 156 and your good to go..
Pete, won't a 72V motor provide the same speed at a lower voltage than a 156 motor would?

Based on my experience, my 144V motor would not be able to get to 40 mph on just 72V, even in 4th gear. But you said you were able to do 65 mph in your ghia on 72V, I assume because that is what the motor is wound for.
 
#13 · (Edited)
Cool thread since I'm going through the same dilemmas...

I keep hearing that it's very common to "murder" the first battery pack. I say start with lead and get it on the road, save up for lithiums. Yeah you do the work twice but keeps you busy in the garage :)

As for the 72V, I'm in the same boat as well. As gottdi said, plan your battery boxes for expansion because it will almost be certain she will ask for more power, thus you will need to go to 96V.
 
#16 ·
Some quick back of the envelope calcs show rapidly escalating cost if I go 72v, lithium battery powered with a controller and motor that can be upgraded to 96v in the future (Extra cost of roughly: $2k in batteries, $900 on motor, $1k on controller, $200 on charger). I don't know if it would still be "on the cheap", but I do understand the reasoning and it is a significant dilemma.

I hope to have it figured out and parts ordered by the end of February - I doubt I can find $4k in a single month, but I will start looking!

It sounds like there is general agreement that the best single item splurge would be to go with lithium batteries - I understand they require different chargers, but do they require battery management systems?

Is there any sense in looking for a motor that offers more HP at 72volt, or is my controller/amperage going to be the controlling factor on speed (at 72v)?
 
#17 ·
It sounds like there is general agreement that the best single item splurge would be to go with lithium batteries - I understand they require different chargers, but do they require battery management systems?
Well, no... but yes!!.:rolleyes:

Some guys drives her lithium pack without BMS and some others with BMS.... you can find many debate on forum...

I personnaly use a BMS because I don't need to care about battery. My BMS stop the charger when single cell hit 3.6v and advertise me if a cell go too low. So, I simply plug my charger each day and I forget about it.
Great advantage for your wife.
I think the Mini BMS is a really good and simple one. For 72v (24 cells) you will need 24 cell module (294$) and a master module (30$).
You can also buy a simple ''fuel gauge'' for 189$ (Absolutely usefull if you ask).

Is there any sense in looking for a motor that offers more HP at 72volt, or is my controller/amperage going to be the controlling factor on speed (at 72v)?
You will be limited by controller voltage. Because top speed is related to power = Volt x Amps.

Bigger motor don't produce more power if controller don't supply more power. Bigger motor can only take more amps for longer time, so with a fix 72v they can produce higher power for longer time than a smaller motor.
So I think you will need to choose between 72v systems and forget about highway or going for a 120-300v systems for more power.

An interesting link here about 72v conversion: http://www.diyelectriccar.com/forums/showthread.php/72v-systems-small-car-68596.html
 
#18 ·
See, i warned you about the others on this forum..... The venerable Curtis forklift controller also comes in different voltages, and there are cheap 96 to 144 v other controllers also ( none of which were mentioned. SURPRISE!!). I think there may be a paul and sabrina DIY controller for sale still over in classifieds. A used forklift motor can be had for scrap value {look over in the motor subforum at the sticky at the top} so actually the major expense will be for whatever battery choice you desire. I do recall the words "on the cheap" in the title and responded accordingly with my caveats.

The important thing is to do the conversion and feel good about it when you drive it quietly down the street.
 
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#22 ·
VW never offered a 3.44 R&P in a type 1 transaxle. I found it at Rancho Transaxles, where you get your? Did you have the shop build you a complete transaxle, or did you have another shop install it into your box?

I have low gearing with a 4.375 R&P. The tires are a bit taller than stock but it is still 3000 rpm at 60 mph in 4th.
 
#23 ·
I have a similar 71 with a half converted Wilderness 72vdc package. I've not been happy with Wilderness and have gone elsewhere since. I've installed Trojan 6v. I would buy good wire, not welding wire. I've also got a battery that has a separate 12v charger, but it's not ideal. With the original batteries and wiring, the car was sluggish and poor range, but with the 6v pack it does great around town and up to 45 mph.

I'm trying to sort out DC/DC Conversion now.
 
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#24 ·
You need at minimum a 96 volt setup for decent around town driving pleasure and a decent controller that will give you better than 500 amps if needed.
I generally agree with that. Have you ever driven a 36 HP Bug Pete? I've driven a couple and they drive nicely around town (suck wind on the freeway.) In that vein, a light Lithium powered car could likely be quite acceptable with a 72 volt system. Perhaps a 24 cell system with a Altrax and a motor that will give decent rpm per volt. The goal is to make sure the peak power is around 3000 rpm. The car would have about 34 horsepower and the 36 HP Bug engine was only about 30 HP net. I would recommend an adapter with clutch because this package would be shifted just about like a stock Bug. I prefer more power with a broader power band and to ditch the clutch, using just 1 or 2 gears for everything. You can't always afford all you want though.

A good DC/DC converter for a basic vehicle like the VW can be purchased from Kelly Controllers and be sure you get the one that outputs the 13.6 volts.
That is what I'm using and it has been working well. They make a 72 volt version too. The price is right, mine where less than $200 each including shipping from China (96v version when I ran 32 cells, 108v version for the current 38 cell pack.) I have never pushed the Kelly DC to DC outside of its rated input voltage range. Some DC to DC converters can be damaged if run under the rated supply voltage and I don't know if the Kelly is such a converter.

I am still of the opinion to go with Lithiums and go with the largest AH cells you can buy. For a 96 volt setup that would only be 30 cells and $7500 for 200 AH cells that would outlast the vehicle three times over or better. Your distances would be excellent and you would have plenty of poop to scoot around. Much lighter than with lead acid too.
I second the recommendation to run Lithium if at all practical. Perhaps a smaller pack using 100 amp hour CALB cells. Even a little pack of 24, 100 amp hour cells should provide a range of 30 miles. It is larger than the pack I ran last year (32, 60 amp hour TS cells) and I had a 30 mile range in the summer. The pack cost would be only a little over $3000. Even better would be 96 to 120 volt pack of 100 amp hour cells for $4000 to $5000. Everybody has a different amount of money they can work with -- I would encourage them do what they can with what they have. If you really want an EV then a slow EV is better than no EV.
 
#26 ·
Pete gave you the low-down on the Freeway flyer so I thought I would toss out a low-cost option. Since your bug is a '69 you can grab a used '72 up Super Beetle transaxle. It will have a 3.875 R&P with a slightly lower 0.93 4th. The overall gear ratio in 4th is almost identical to a Bug with a 4.125 with a 0.89, but the first 3 gears will be a bit taller and since EVs have lots of torque taller can be better. With a little scrounging you might find a good used box for cheap.
 
#27 ·
What is a second choice motor if I can't swing the netgain motor and am still in the 72 volt camp with a possibility of someday going to 96 volt?

Again, the car is an around town grocery getter. The grocery store is 2 miles away on 25mph roads with 2 stop signs. Work is 4 miles away on 30mph roads (a small stretch of 30mph road where everyone drives 40 mph) with 2 stop signs and 4 traffic signals. There is one 45 mph road in town that the vw may occasionally use. There are no hills. Prevailing winds are from the west, and 80% of the driving is north/south.

I did do some searching on the forums and see a lot of useful in depth info for what I would call high-end home brewed electric cars. The garage feature is especially sweet - several vw case studies and anice search setup. Still learning alot and dialing in my budget. Thanks for all the input, it is trully helpful on several levels.

Also, I ebayed some marine 2/0 gauge copper wire for wiring - $85 shipped for 25' - Will this cut it for my wiring needs?...

And I am also done welding up floorboard holes and almost done welding up the dashboard for backdating to an all steel dash...
 
#28 ·
Super transaxles are a dime a dozen - I am sure I can find one cheap in my local vw club...is it a bolt in conversion or does it require some modification?

When I bought the bug, I got a second IRS axle that I intend to put in my '65 sunroof beetle to replace the swingaxle - the '65 beetle was going to be the electric conversion beetle - I have the body stripped, replaced the heater channels and floor pans and was getting ready to paint it this spring, but then this '69 beetle came along...so now I have a half restored '65 beetle that is hogging garage space that I need to complete and sell - it could fund some future electric car upgrades...
 
#29 ·
so I quick search in the bentley book shows for all beetle/superbeetle models:
1st: 3.80 (pre 1973)
1st: 3.78 (1973 and later)
2nd: 2.06 (all models)
3rd: 1.26 (all models)
4th: 0.89 (pre 1970)
4th: 0.88 (1970 to 1972)
4th: 0.93 (1973 and later)
final drive: 4.375 (pre 1970)
final drive: 4.125 (1970 thru 1972)
final drive: 3.875 (1973 and later)
 
#30 · (Edited)
To install a Super Beetle transaxle in an older (but IRS) Bug you will have to use your transaxle nose cone due to a change in the front mount after 1972. You will also need to use a newer type pressure plate and throwout bearing. I can't think of anything else and I'm sure others will chime in if I forgot something.

It's that 3.875 R&P you may want (I do.) My buggy is swing axle so it isn't so easy. In theory, the taller the R&P the more efficient it becomes.
 
#31 ·
In a world of limited budgets, would you upgrade a transmission or upgrade a motor/controller assuming that you have 72 volts to work with?...

Also, while on the subject of transmissions, I intend to go clutchless, which means the motor can spin freely if it's not in gear.

It looks like some controllers offer protection circuitry - does this protection prevent the motor from spinning to fast in an unloaded condition? - I could see this becoming an serious safety issue if say the cable to the throttle box gets stuck and the driver needs to shift into neutral to come a stop. It could also be an issue if the driver misses a gear or has a brainfart...
 
#33 ·
It looks like some controllers offer protection circuitry - does this protection prevent the motor from spinning to fast in an unloaded condition? - I could see this becoming an serious safety issue if say the cable to the throttle box gets stuck and the driver needs to shift into neutral to come a stop. It could also be an issue if the driver misses a gear or has a brainfart...
You could fit an aftermarket tacho with a shift light.
Set the shift light to come on at just below maximum safe motor speed and use the shift light circuit to trigger a relay that cuts the controller/throttle off.

That will protect the motor from overspeed under power (in neutral or in too low a gear) but it won't help if someone rolls down hill fast in first gear.
You could even fit micro switches on the gear selectors to cut the controller/throttle circuit when in neutral.

You might find that it drives ok in 2nd and 3rd gear so you could lock out or remove 1st gear for a bit of over speed safety.

With the voltmeter and ammeter, if you think your wife won't want to look at them you could fit them for your eyes only, in the passenger seat, or in the engine bay for diagnostics in the garage.
 
#32 ·
I would make sure to pick a good motor and adapter first. Then I'd pick a better controller, then I would get around to changing the VW transaxle to adjust gearing. The gearing change won't be that big, most likely from 4.12 to 3.88 in the final drive. I am still running my transaxle with the 4.37 final drive (40 horse gearing.)

Motor controllers can only limit power applied to the motor to limit rpm (and only some can do that.) If you coast down a hill in 1st gear and hit 35 mph you will likely blow up the motor. There is no DC controller I'm aware of that can do anything about that.
 
#34 ·
Motor controllers can only limit power applied to the motor to limit rpm (and only some can do that.)

If you coast down a hill in 1st gear and hit 35 mph you will likely blow up the motor. There is no DC controller I'm aware of that can do anything about that.
So yes, some of the better controllers can prevent overspeed (in neutral) if properly configured. There is also the risk of overspeed in 1st or 2nd at higher speeds. IE you can't run 144V to get 55 mph in 2nd with some motors as that is around critical RPMs. In Neutral is neutral so doesn't matter (if not applying throttle). I have heard of one guy that tried to tow it in neutral and it (apparently) slipped into gear on the highway and made the motor explode.
 
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