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Discussion Starter #1
Hey all,

This will be the conversion thread where I ask (hopefully) not-too-stupid questions and post pictures of the things I've broken.

GOALS
Top Speed - we'd like to get 70-80mph for the headroom of it. We live in Southern California - everything is highway driving here.
Range - in a perfect world, we'd need a minimum 50mile/80km range highway driving without too much drain on the batteries if we take it that far. My wife would like to occasionally commute this to and from her job, which is about 48 miles one way with probably 40 miles being highway driving.
Conversion Cost - MAX $10k, and would prefer to be well below that. I have a decent amount of mechanical experience and electronics experience (I design & build recording microphones for a living), and I'm going to pick up welding to avoid costs there. I can get the CNC adapter plate done for relatively cheap with some contacts I have from my job. I'm not sure if what I'm trying to do is achievable with that budget, but there you have it. We've got plenty of body work that needs doing on the car as well - it's been...well-loved. A brand-new strip-and-seal-and-paint, lots of ding repair, some welding of cracked fenders, etc. is definitely in the cards. We've got some parts we'll sell off to help offset the conversion costs, including a working engine that needs a bit of love and some original and modded parts we'll be discarding. We're not too upset that it's not all original, because the one we bought needs a LOT of work to make it original again.

DONOR CAR - 1971 VW Super Beetle in Clementine Orange

2018-10-20 16.03.56-2.jpg

Bought the donor car a few months back but have been trying to finish other projects before this one consumes all my time. Has new front shocks, needs new back ones. The car is pretty darn rust-free. The poor kid who sold this to us was planning to do an ICE restore, but lost his scholarships and had to pay for another 2 years of Cal State. We paid a bit more than what it's worth, but I frankly felt rather bad about it.

MOTOR AND CONTROLLER

I'm really liking the idea of using an AC motor for the various performance benefits like regen braking, etc. but it seems like finding a really decent DC motor and controller shouldn't cost too much (I have a few forklift repair shop contacts I can ask). A lot of the builds I've seen on evalbum and elsewhere use DC motors for their builds and get really solid speed and range.

Here come the first stupid questions:
1) What are some tips for finding an affordable 3-phase AC motor, used or new, for EV conversions?
2) Is it realistic to think I can find a controller/inverter/VFD that will be able to match to a AC motor online?
3) If I go DC, is it feasible to find a forklift motor that will be able to achieve my top speed goals?

BATTERIES

As our range dictates, I'm pretty much forced to go with a LiFePO4 option or find some lightly-used battery packs from car-parts.com or another source. This is no doubt going to be our highest expense; I'd love to get 20kWh minimum.

More dumb questions:
1) I see a lot of people touting "range", but obviously range goes down significantly at highway speeds. This is where an AC motor comes in handy in terms of higher range at higher speeds, correct?
2) What is a rough approximation of kWh needed in the battery pack to get the range we're looking for? For LiFePO4, what's the maximum DoD to keep the batteries fresh?


Charger, shunt, etc. are all not decisions I need to make currently, so I'm not too worried about those at the moment as the battery and motor decisions will have large impacts on some of the other parts.

And, here's some VW pr0n because if I didn't put pictures in this what's the point, right?

Jack checking out his new ride.
2018-09-15 17.58.37-1.jpg

The wiring is a mess. We were having battery drain problems when we got it home, and that's not surprising given that there were disconnected leads willy-nilly in the front compartment.
2018-11-03 16.27.50.jpg

2018-09-15 17.57.07.jpg

We've since pulled everything but the seats, the ICE/gearbox and assorted components involved therein, and the gas tank. we'll be having to do some major bodywork and obviously a repaint as well.
2018-11-03 16.57.30.jpg
 

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Discussion Starter #2
I realized that I didn't quite fulfill all the questions in the sticky:

Your skill level with auto mechanics and fabrication

I do most of my own auto maintenance and repair, but by no means am I a pro mechanic. I'm very much a "learn-as-you-go" and I've got the tools and YouTube/Google, which in this day and age means you can do anything if you give it time and effort. But I've done rotors/calipers, brake changes, misfiring cylinder diagnostics, alternators, etc. with no problem on my cars since i first started driving and realized mechanics are really making a killing at $250 when spark plugs are $5 a pop and you've got an easy-to-access straight-4.

The range you are hoping to get (how many miles/charge)

minimum of 50 miles per charge, ideally 75-100 without wrecking the batteries. I've looked at other Beetle builds and it's likely I'll need at last 16kWh for that.


What level of performance you are hoping to get

at least 70mph (highway speeds), with regen (in a perfect world)

How much money you are willing to put into your project
We're trying to do it on as much of a budget as possible (we've also got a sick dog to look after) but looking at around $10k

What parts you've already considered, if any.
For the motor, we're looking at both DC and AC options. 3-phase AC really seems to be the way to go, but I've had a lot more ease of finding DC motor options vs AC. I'd love to just go out and get a Curtis AC-50 and accompanying controller and batteries and a whole kit, but that's pretty steep and well over our budget if we go to a place like EVWest. Plus, as a DIYer, I'm alway up for the adventure of the build.

For controller, well, that depends entirely on the motor.

For the batteries, I'm hoping I can snag some Volt or Leaf batteries out of salvage and kludge them into a battery pack.
 

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Discussion Starter #3
Pulled the engine yesterday. Have a question for those who have done a Beetle/Super conversion:

Do you pull the old fuel line and other assorted ICE lines completely out of the car, or just chop the line and not worry about trying to extract it?

DROPPING THE ENGINE
1858074.jpg

I HALP.
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GOODBYE, I.C.E.
1858062.jpg
1858067.jpg

Anyone know what I should list this ICE for?
 

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Hi
For a budget of $10K

You could do that with DC - and a Volt pack - I spent about $9K

Or you could get a crashed Leaf and use all of it's bits

What you probably can't do on that budget is any sort of new AC units
 

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Discussion Starter #5
Hi
For a budget of $10K

You could do that with DC - and a Volt pack - I spent about $9K

Or you could get a crashed Leaf and use all of it's bits

What you probably can't do on that budget is any sort of new AC units
Hi Duncan,

did you do yours in a VW bug as well?

As far as DC - what motor are you using, and why did you choose it over AC?

Thanks!
 

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This is a response to a post in other thread, but it's about the battery and that thread is about motor selection:

I'm already planning on a battery salvage because otherwise batteries alone to get 20-24kwh is just a bonkers expense...I'm really curious about how they'd fit when it comes to a VW Bug.
The common battery pack locations in a Bug appear to be
  • the parcel shelf, and
  • under the front hood (in place of the fuel tank and/or spare tire, and/or storage space).
I find it interesting how rarely anyone seems to use the spaces on each side of the motor; there should be some space available there since any electric motor is so much narrower than the flat-four engine (assuming the motor is mounted as intended in the same location and orientation as the engine was). The problem is likely that battery modules have rigid dimensions which are unlikely to fit with those small spaces.

All of these locations have issues accommodating large masses of battery... although the issues are different.

For battery housing design, I note that the parcel shelf space is in the vehicle interior with the people, and the engine compartment space is exposed to the outside.

In any case, if the battery needs liquid cooling then space must also be allowed for the cooling system.
 

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Discussion Starter #8
Hi
No not a bug

https://www.diyelectriccar.com/forums/showthread.php/duncans-dubious-device-44370p15.html?highlight=duncan

I'm using an 11 inch Hitachi Fork lift motor - which cost me $150

Nice! I assume the controller was a bit pricey?



I'm still waffling between AC and DC on a daily/hourly basis. DC can be done on such a great budget, but AC has the ease of regenerative braking. We're trying to get 100 mile range and obviously DoD is a factor for making sure the batteries stay fresh as possible. My wife wants to take it to work occasionally which is a 50-mile drive (part traffic, part highway speed...this is Los Angeles area, after all...)...so I know I need to do as much as I can to get range, including battery pack size AND the efficiencies involved in a good AC motor. Also, the top speed is DEFINITELY a factor. 65mph is a minimum as people drive like maniacs out here...
 

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Hi
I started with a Paul & Sabrina 500 amp controller - that gave me about 100 hp - probably enough for a bug - and the kit cost about $600

I'm now running a P & S 1400 amp controller (set to 1200 amps) - mine is a Beta version from Paul but it would cost about $1000

I do like the P & S approach! simple solid and work superbly

Re-gen only buys you a small amount - and other than re-gen a DC motor + controller is about the same efficiency as an AC motor + controller

If you drive like a hooligan then re-gen can help a lot (why taxi drivers like it)
But if you drive normally don't expect much of an advantage


IMHO it goes like this
Best - and cheapest
Motor and controller from an EV - I think P & S do a control board for a Leaf
Next
DC motor from Forklift
Next
New AC motor and controller
Last
New DC motor and controller
 

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Discussion Starter #10
Hi
I started with a Paul & Sabrina 500 amp controller - that gave me about 100 hp - probably enough for a bug - and the kit cost about $600

I'm now running a P & S 1400 amp controller (set to 1200 amps) - mine is a Beta version from Paul but it would cost about $1000

I do like the P & S approach! simple solid and work superbly


IMHO it goes like this
Best - and cheapest
Motor and controller from an EV - I think P & S do a control board for a Leaf
Next
DC motor from Forklift
Next
New AC motor and controller
Last
New DC motor and controller
Re-gen only buys you a small amount - and other than re-gen a DC motor + controller is about the same efficiency as an AC motor + controller

If you drive like a hooligan then re-gen can help a lot (why taxi drivers like it)
But if you drive normally don't expect much of an advantage
It's not about driving like a hooligan so much as Los Angeles area having a LOT of stop-and-go traffic. We live about 40 miles from LA, and it's still brutal out here. The traffic is just...everywhere, at all times of day, at this point. I remember as a kid you'd have to avoid the highways for around 1.5-2hrs around rush hour. Now, it seems there's a 4-5hr "rush hour window". It's ridiculous.

Best - and cheapest
Motor and controller from an EV - I think P & S do a control board for a Leaf
Next
DC motor from Forklift
Next
New AC motor and controller
Last
New DC motor and controller
Motor/controller from EV would be great if our '71 Super Beetle could take something as large as a Nissan Leaf engine. Even the old ones look like they'd have trouble fitting into my engine compartment without some serious modification. I have yet to find someone using the Leaf motor in a Beetle, but I'm sure I'm about to be proven wrong :D I'm looking at some other EVs like the Kia Soul and Chevy Spark to see if I can find something that might fit properly.

I'm looking at forklift motors but would need to run them at a minimum of 120V for highway speeds in California 65mph/105kph. That's a minimum...people drive like maniacs here. If you're doing the speed limit of 65mph, you're going "too slow" by many people's standards.

Thanks very much for your info. I'm basically absorbing as much as I can like a sponge until I form some sort of coherent plan :)
 

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When I had a 130v battery my max speed was 100 kph - my Device is not very aerodynamic but at 100 kph it required 200 amps and with 130 volts and the controller at 100% that was what I got!

I would say your minimum voltage should be around 150v

Don't worry about the fork lift motor voltage - they can take a LOT more than they do in the forklift
 

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Discussion Starter #12
When I had a 130v battery my max speed was 100 kph - my Device is not very aerodynamic but at 100 kph it required 200 amps and with 130 volts and the controller at 100% that was what I got!

I would say your minimum voltage should be around 150v

Don't worry about the fork lift motor voltage - they can take a LOT more than they do in the forklift
Ends up looking more and more like I'm going with the salvage LEAF option.

Between P&S and a few clever folks who have hacked the leaf controller, I can see this being the most budget-friendly option.
 

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LOOONG time between updates, but here we are.

After some fiscal constraints, we're working on finding a salvage Nissan LEAF. In California, this has been far more challenging than I expected. The interest level in Leaf battery packs has rather increased, which has led to higher sale prices. Our initial budget expectation was around $3000-3500US for a salvage Leaf, with all fees. I haven't seen them below $4000 before auction, gate, etc. fees at Copart and IAAI, which would bring them to around $5000 total. Getting them delivered from out of state isn't any better.

My second idea was just to attempt to buy the drivetrain and batteries separately for around $3000-3500US, but I feel that it's likely I'll be needing some other parts from the Leaf I don't realize yet (throttle! coolant! magic wand!) and the costs will just add up.

The other challenge is finding a 2014 or newer model Leaf with the "Lizard" battery chemistry. We live about 50 miles east of Los Angeles in Upland, California, and temperatures here routinely hit above 100F on summer days. (My initial and exceedingly ambitious thought was to add some sort of TMS to my Leaf battery configuration, but that adds another layer of complexity that I'm not ready for).

Using this thread as sort of an open diary, I'm currently sussing out how to get through a few problems.

Coupling the Leaf motor to the Beetle transaxle

Between CanEV plates, Jeff Black's very cool adapter and coupler, and my own ability to do CAD work and source CNC parts for my business, I feel I can likely couple the Leaf motor to the Beetle transaxle. There's certainly some steps to this I'm not thinking of, but I feel this is more within my wheelhouse than option 2.

My second option is to somehow pull the Leaf's existing "gearbox" reducer from the donor Leaf, and getting rid of the old Beetle gearbox. This maintains the Leaf's original gear ratio. The question is mating the Leaf "gearbox" with the Beetle axle. I expect some significant fabrication would be required. That sounds 1) expensive and 2) outside of my purview.

I'm not sure which is easier, more cost-effective, and reliable. Both options I can see having significant pitfalls.

Spoiler alert - I'm not a huge car guy, but I typically do work on all my own cars as a mechanically-minded person. I'm not knowledgeable about anything in a car until I NEED to be knowledgeable about it (thanks, Internet!). I've never worked on a transmission and many of my assumptions here could be wacky. Feel free to correct me and/or make fun of me.

Cooling the Nissan Leaf drivetrain components which are liquid-cooled - on-board charger, DC-DC converter, motor inverter, and motor.

The Leaf uses liquid cooling, and the old Beetles are famous for being aircooled.

I'm going to HAVE to split the drivetrain stack of the Nissan Leaf into separate parts. The Beetle engine bay is just too small.

OPTION 1: bolt controller, inverter, etc. to large aluminum cooling plates in the engine bay, as is the norm with most Beetle EVs I've seen. I'm not certain if this will be enough cooling for the Leaf drivetrain. Any Leaf conversions have any experience with running the Leaf motor w/o liquid cooling?

I can also wire up some fans + temp sensors to run off the 12V battery system and provide additional cool air to the engine bay.

OPTION 2: rig some tubing that will use the Leaf's existing coolant system and extend it around to the various components in the bay. That seems...complicated. I'd REALLY prefer if someone had run them air-cooled and told me it works just dandy.

Climate control!

As I mentioned before, it gets HOT here...we had a few days last year that topped 115F/45C. I'd rather be able to drive our Beetle without sweating through all my clothes. In addition, I feel that extending that climate control under the front hood (where the majority of the batteries + BMS will reside) seems like a smart option for maintaining battery integrity.

From what little I've read about the Leaf climate system, it's "complicated". I'm not sure if this means that I should attempt to use/salvage that system (not even sure if that's possible using the P&S controller) or just find an alternative for climate control?
 

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For using the whole Leaf drive unit (replacing the VW engine and transaxle):

In case it's not clear, using the Leaf gearbox instead of the VW gearbox effectively means using the entire trasverse Leaf transaxle (reduction gearing plus differential) in place of the entire VW longitudinal transaxle.

I believe that the Super Beetle (or 1302 model) had CV joint axles; if so, adapters can be built, and Yabert's Vanagon/Bolt project illustrates this. With the swing axle suspension the axle shafts are part of the suspension arms, putting lateral forces into the transaxle, and the Leaf transaxle isn't suitable for that.

The bigger problem is that it seems unlikely that the Leaf drive unit would fit in a Beetle without hitting structure, since it places the motor transversely and ahead of the axle line; it would be in the parcel shelf behind the rear seat, not in the engine compartment. The Bolt drive unit fit in Yabert's Vanagon (which came with a Beetle-like engine and transaxle), but the van and Beetle are structured differently, and the Bolt motor is on the axle line, not ahead of it.
 

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My second option is to somehow pull the Leaf's existing "gearbox" reducer from the donor Leaf, and getting rid of the old Beetle gearbox. This maintains the Leaf's original gear ratio. The question is mating the Leaf "gearbox" with the Beetle axle.
Re-reading this, I wonder if (depending on what you understand "axle" to mean) you are proposing to somehow split the VW transaxle into two sections, retaining the final drive section (which contains the differential), plus split the Leaf transaxle similarly, then merge the reduction gear section of the Leaf transaxle with the final drive section of the VW transaxle.

If so, the short answer is "no", assuming that you do not have the abilities and facilities to build transmissions from scratch.

It would be far easier to just use the VW transaxle and leave it in one gear (presumably first or second) to get the right overall ratio.

Another alternative is
  • remove and not use the VW transaxle at all, and
  • not use the Leaf transaxle at all, but instead
  • mount the motor to a final drive unit (differential in housing with ring and pinion gears) with no other gearing
The gearing would be wrong, but if you choose the right final drive you might find a ring-and-pinion set with a high enough ratio (not the 7:1 that you want, but close enough). Amusingly, this is what the Palatov Pike's Peak race car has (as well as various earlier race cars using similar motors)... but they want to be geared for much higher speed than the Beetle, so the ratio works out for them.

The Chevrolet Spark EV (mentioned earlier) has an unusually low-speed/high-torque motor, so would be suitable for this setup with only one stage of reduction gearing... but you would need to either find a controller/inverter which works with it, or be (probably) the first person in the world to figure out how to use a Spark EV controller outside of a Spark EV.
 

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Cooling the Nissan Leaf drivetrain components which are liquid-cooled - on-board charger, DC-DC converter, motor inverter, and motor.

...

OPTION 1: bolt controller, inverter, etc. to large aluminum cooling plates in the engine bay, as is the norm with most Beetle EVs I've seen. I'm not certain if this will be enough cooling for the Leaf drivetrain. Any Leaf conversions have any experience with running the Leaf motor w/o liquid cooling?

I can also wire up some fans + temp sensors to run off the 12V battery system and provide additional cool air to the engine bay.

OPTION 2: rig some tubing that will use the Leaf's existing coolant system and extend it around to the various components in the bay. That seems...complicated. I'd REALLY prefer if someone had run them air-cooled and told me it works just dandy.
Two things that I find unlikely, although this is just my guessing:
  1. that the Leaf components would cool properly if just bolted to a heat sink plate, and
  2. that it would be easier to build an effective cold plate system than to just hook up the coolant lines for the system that Nissan already designed
The Leaf cooling system is somewhat sophisticated, presumably with some integration with the HVAC (heating, ventilation, and air conditioning for the vehicle interior) system, but to just operate the electronics safely you don't need that. Some tubing, a suitable radiator with a thermostatically-switched fan on it, and an electric pump, and you're in business.

This is assuming ultimate maximum performance is not the target. If it is, then liquid cooling is essential... there's no Option 1.


Perhaps more importantly, the motor is liquid-cooled, so you need the circulating coolant and a radiator anyway.
 

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Climate control!

As I mentioned before, it gets HOT here...we had a few days last year that topped 115F/45C. I'd rather be able to drive our Beetle without sweating through all my clothes. In addition, I feel that extending that climate control under the front hood (where the majority of the batteries + BMS will reside) seems like a smart option for maintaining battery integrity.
Since lower temperature isn't always better for the battery, I suspect that trying to cool the battery along with the interior might not be easy to work out well. Why not just provide fan-forced air circulation for the battery, controlled by a thermostatic switch? That's more than Nissan does in the Leaf.
 

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Discussion Starter #18
Ends up looking more and more like I'm going with the salvage LEAF option.
Alright, about to pull the trigger on a Leaf (2011 with only 25K miles) from CoPart.

However, I did want to ask a pretty important question:

I have to buy the car sight-unseen, unfortunately. Knowing CoPart employees' reputation for stealing valuable stuff off cars - does this photo indicate the batteries are STILL PRESENT on the car?

leaf8.jpeg

(I see the degradation of the batteries, but not much I can do about that. More interested in if they're actually THERE.)
 

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The 2011 batteries are not known to be all that robust...They seem to diminish rather quickly. Unless they're much cheaper than 2013+ sleds I see going for $3,000-4,000, it might be worth waiting if it doesn't hold up your project. My wrecked Leaf was $5,500 when all was said and done, but it was driving fine when I bought it.

The 8:1 Leaf reduction will get you to about 100mph with 25.4" tires, which is higher than you want, but I think you'll be fine leaving some acceleration on the table! Direct-drive would save weight and complexity over keeping the existing transmission, though the tricky bit then becomes packaging. Having a transmission is nice to fine-tune the final gearing...until it breaks or leaks...I'm in a similar boat with my Rover Mini project, and I'm currently asking around some race/fabrication shops to see who might be able to fab up some motor mounts.

These folks apparently make custom axles, but I don't know how accurate the specs need to be (I assume axles require quite a bit of play/slush, but I haven't gone down this road yet).

https://www.driveshaftshop.com/

Here's my thread on getting Leaf components to work...It's looking more and more like I'll have to abandon this approach for aftermarket components. I failed to document the wiring, connectors, and components exensively enough, and I just can't figure out why I can't get the "car" to "start" now that it's outside the chassis:

https://www.diyelectriccar.com/forums/showthread.php?t=199847

On the upside, it seems like a lot of the Leaf components have had their CAN BUS stuff figured out, but...I'm looking for products as opposed to plans for an Arduino that I'd have to build and program myself. There is a lot to be said for buying a drivable car, 'cause you know if it doesn't work when it's a apart it's something you missed...You can also use LeafSpy and a wireless OBD reader to get a really good sense of the battery pack health.

Oh yeah, and these VW conversions are EV West's bread and butter, so...Might be worth scrutinizing some of their builds, if you can.
 

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Hi Trelmelune

I hate to say this but you may be better just groveling to the wife and buying another Leaf -
In the hope that eventually you may be able to sell off the spare bits
 
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