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As a teen in the early 90's, my first car was a 1973 VW Super Beetle (ess desirable than a standard beetle).
I loved it. Even to this day, I'm super familiar and still a fan. It's how I learned to turn wrenches, and to this day I still DIY my car whenever I can.
It also started my DIY car audio hobby, which went off the rails into an Electrical Engineering college major (which I never finished, only because opportunity with a college job led me to IT and the pursuit of that degree), then professional work in fabrication, car audio engineering work, AES associations... at any rate, I actually enjoy disassembly/reassembly, fabrication, and pushing limits and boundaries, and getting creative.

I'd like to sell my current fun car in the spring, and buy a solid Super Beetle to do the equivalent of a ground-up refresh.
I'm too old to settle or get into lengthy discussions about "why" with people, so I would love to have all those questions answered when I put my right foot down. 馃榿

Initially, I had considered a Subaru swap (believe it or not, turbo boxer engines fit in the back of Bugs), but I think an electric conversion would make for a more fun, more current, more relevant "fun car" conversion.

I have lots of homework to do, but I know batteries are a big cost driver. It's even what seems to separate one Tesla model from the next, besides single/dual motor and subscriptions. I know if I built the equivalent of "an electric drag car", that my battery life would be pretty short, which would limit my alternative desire for a fun weekend cruiser.

It makes me wonder - if I built my own battery packs - could I use some high-current capable relays to change the series/parallel relationship of the packs, to change the overall system voltage? Throw a switch one way, high-voltage "Drag mode". Throw a switch the other way, lower voltage "Drive mode". I don't know if it works out this simply, but the idea would be along the lines of "2x the voltage = 2x the hp, but 1/2 the mileage"

I was also considering buying a spot welder and making my own battery packs, because - like in car audio - I like to fit things into voids, to take advantage of that space while keeping things practical, and that could suit that plan as well.

At any rate, lots of homework to do. I will likely split this up like a project, in phases, as there's the electric powertrain to complete, the car itself to complete, and the interior and technology to complete.

Any pointers in the direction of any threads that have already discussed the electric powertrain topics would be great.
I've tried to find some good VW conversion threads, but most seem to target just "making a VW run on electric power" rather than really using the VW's lightness for all that lighting speed potential, and maybe even handling improvements if I can locate the packs down low.

I would like to do a conversion that generates envy in the car-guy circles (I can make it look nice enough for the car show circuit), rather than perpetuate the old electric car conversion golf-cart stereotypes. Maybe some crazy multi-voltage approach isn't necessary, but I'd like to change some minds. I'd like to turn it around and make them wonder why they have a V8 in that Chevelle.

I'm hoping this plan isn't a non-starter.
 

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It makes me wonder - if I built my own battery packs - could I use some high-current capable relays to change the series/parallel relationship of the packs, to change the overall system voltage? Throw a switch one way, high-voltage "Drag mode". Throw a switch the other way, lower voltage "Drive mode". I don't know if it works out this simply, but the idea would be along the lines of "2x the voltage = 2x the hp, but 1/2 the mileage"
This idea was used a few years ago, not for "drag" versus "street", but to switch from low-voltage/high-current at low speed to high-voltage/low-current at high speed. With modern motors and controllers this is no longer useful - just configure for the highest voltage you need and let the controller handle the conversion when less voltage is needed.

Reconfiguring the battery won't change the efficiency of the system, or increase the power available from the battery.

When you get to the point of designing the system in more detail, you could look at the high-voltage configuration and then ask the question: why can't this provide the high current desired at low voltage? I think you'll find that the answer is only the current rating of the controller/inverter.
 

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I was also considering buying a spot welder and making my own battery packs, because - like in car audio - I like to fit things into voids, to take advantage of that space while keeping things practical, and that could suit that plan as well.
It's a lot of work to custom-build packs. I think it makes more sense to choose a relatively small available module (so a lot of modules will be required) so they can be arranged to suit the space, without custom-building modules. Of course, you can do whatever makes it the project that you want. :)

One member here (tiger82) has built two customized battery packs for a race car, using first Kia Soul EV module components, and then Chevrolet Bolt module components:
Tesla Powered Cobra Race Car
Modified Bolt Pack for Tesla Cobra EV Race Car
 

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I'd like to sell my current fun car in the spring, and buy a solid Super Beetle to do the equivalent of a ground-up refresh.
Do those still exist? ;) A friend of mine has restored a couple of VW vans, and what he has learned is that due to the age of these vehicles and their popularity among people with lots of money to spend, parts are expensive. You could probably build a Corvette for the same cost. Perhaps the choice of the less popular Super Beetle (1302/1303) will help.

The Super Beetle will at least it will give you more space in the front for battery and other components, and will presumably have the CV-joint rear axle, which would mean that you are not restricted to the VW transaxle needed to work with swing axles.

Of course, build what you want... just be prepared for significant cost.
 

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Echoing Brian's sentiments...

The VW bug has a few kits, and I would recommend shelling out for one if at all possible...I'm not sure if buying this full kit is the way to go, but certainly anything that would require fabrication is better purchased off the shelf (unless you're a great fabricator):


I'd get the motor, controller, adapters and what not, and source batteries from a wrecked Leaf. You'll never build cheaper batteries than those, and they're pretty good batteries. Get a car on the road before thinking about lengthy optimization.

For a highway-capable car, it's hard to beat a real-world estimate of about $15k in parts at the moment. The nice thing about electric classics is that, if they have the batteries to do 50mi of range, they can also smoke the tires...Torque is abundant, even with the modest AC50.

There are a lot of ways to skin this cat, but no slam-dunks. It's all trade-offs between parts cost, labor effort, and weight/space savings.
 

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The VW bug has a few kits, and I would recommend shelling out for one if at all possible.
I think a kit is a good idea too, it's a very popular build. However, I would recommend against dealing with EV West after their 6-month ongoing fiasco with Snowdog. Every part they sent him was broken, they ignored his attempts to contact them for months (still ongoing), just disastrous parts and service level. You don't want to get trapped in that situation.

Get a car on the road before thinking about lengthy optimization.
Indeed. Made up statistic, 9/10 car projects get abandoned. Be the 1/10 that gets it working first, and better later.
 

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It makes me wonder - if I built my own battery packs - could I use some high-current capable relays to change the series/parallel relationship of the packs, to change the overall system voltage? Throw a switch one way, high-voltage "Drag mode". Throw a switch the other way, lower voltage "Drive mode". I don't know if it works out this simply, but the idea would be along the lines of "2x the voltage = 2x the hp, but 1/2 the mileage"
No point.

If your controller can handle the higher voltage, there's no reason not to use it all the time. If it can't handle the higher voltage, it can't handle it on the order of milliseconds, and it'll already be exploded.

You're not correct about energy usage.

Your controller's job is to control how much power goes to the motor. Even flat-lined though, you're limited by the voltage in how much current you can push. So, more voltage means you could push more current.

But you don't have to. Same as you don't have to have the gas pedal pushed all the way down all the time.

The motor doesn't just "waste" energy if you double the voltage the way you might be thinking it would with, say, a lightbulb. So, you'll get the exact same range whether you have 2x the voltage or not (well, 2x the voltage will be a tiny bit more efficient, but otherwise, no difference).

I was also considering buying a spot welder and making my own battery packs, because - like in car audio - I like to fit things into voids, to take advantage of that space while keeping things practical, and that could suit that plan as well.
I'm doing this, I think I've seen 3 others do this. I don't recommend it. It's lots to dick around with. It's lots to go wrong. It's far, far more expensive.

Unless you're really stuck with no other solution in terms of form factor, and cost is no obstacle, don't bother with making your own 18650 pack.
 
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