EV bug conversion

[dabaron]

[kpf]

[gilbertma]

[minimeadow]

Gilbertma, thank you for the great pics and information about your conversion. I think there is room for both purists and modders in this hobby, and your conversion looks very well done.

[Profcucchi]

[prolewicz]

Any reason why you didn't split the batteries between front and rear? Great photos.

Thanks
Pete

[BluemarblePA]

This is a wonderful post. Thank you for showing that this can be done well.

[rayjay]

About 2 years ago I bought a Zero FXS electric super motard motorcycle. For all the haters I have to tell you that the sensations when operating an electric vehicle are UNREAL !! The EV Beetle above has to be an absolute hoot to drive. The WOT acceleration in third from 30 mph has to be amazing. Yes 100 mile range EVs are short range commuters or toys, just like a ACVW. I actually thought about buying a Tesla but the EV for everybody is bs. They are niche items and I bet in the future their dead batts are going to be a problem .

[supersisu]

Hi gilbertma, we just started working on a 67 Squareback conversion for a friend using parts provided by EV west, it sounds like we are following in your footsteps (cardboard battery mockups, etc.). I'm wondering about your battery cooling system: I think I see a pump under the fluid tank? We are debating if cooling is necessary if only slow charging (although it couldn't hurt and could also be used for warming batteries here in Chicago?).

[gilbertma]

Hey there, I still have the electric Super and it just hit 8000 miles on the electric stuff. It's gone through a lot of changes since late 2022, I decided to make it a pseudo- class 11 type car with 29" tires. This necessitated the movement of all five battery modules to the rear, three in the luggage area and one under each seat. The removal of the battery pack (280 lbs) from the front gave me a suspension lift of three inches, which was great, so all I had to do was reindex the rear torsion bars to match. To get all this to work together, I also added a pro-street transaxle with super diff and 4.37 ring gear. This gave me a final drive ratio of 9.0 to 1 in second gear which is close to the Model S ratio of 9.3 to 1 with 28" tires.

So let's talk about the cooling system. My original system was a single loop going from the tank (old windshield wash tank), to the Tesla pump, through the batteries,, back to the motor controller chill plate, then forward to the front mounted trans cooler. This was mounted behind the front apron louvers.
When I added the larger tires I noticed I was drawing more amps, thus creating more heat, so I reasoned that having two coolant loops would work better. So I added a second trans cooler, another Tesla pump, and an old Ghia reservoir to isolate the battery cooling system. The original cooling system remained and was used for the motor controller only. I immediately noticed more water flow through all of the components and reduced controller temps in the summer. These Tesla pumps are all over ebay now compared to when I started and you can find one under $100 now. If you haven't heard of them you should check out Hawkeye Innovations LLC (.com) in Texas, I'm using their System Control Module to integrate my system, the BMS, the 12v battery monitor, and fan and pump control.

I'm not currently running an on board fan, when I'm driving I use ram air and when I'm charging at home I use a fan in my garage. When thinking about whether a cooling system is needed, I have been told it's not about how hot the batteries are, it's more important that they are all the same temperature (and voltage). Now the cold thing is different, lithium batteries do not like freezing temps, something I don't have to worry about in FL.

[mj2k]

Interesting to read about a working converted Super, I got all the parts to do my own EV conversion last year, but then it turned out my Super was a complete rot-box made mostly from rust and Bondo, so I've spent the past year welding it back together with all the EV parts sitting in the garage awaiting fitting

I went for 280Ah lifepo4 (LFP) batteries rather than the Teslas since they're less prone to overheating and don't need a cooling system, but since their power / weight ratio is much poorer than the Tesla packs I'll end up with quite a limited range and I've gone for a motor which isn't very powerful, so it'll accelerate like a plain old 1200!

I did find a rather nice throttle pedal solution from a Chinese source though, and discovered the charging components from a BMW i3 fit rather nicely under the fuel filler, which means CCS ultra-fast charging will be an option when I've sorted out the comms protocols:

Mockup of proposed battery / BMS (battery management system) locations:

Think I might have to rethink my BMS though - splitting the battery pack means the wiring will be nightmarish with my current system, and probably not very reliable.

Still a loong way to go before I have a working EV too - I think there's still another month's worth of bodywork to do before I can even start creating a new loom, let alone starting to fit components...

As for the whole question of converting a bug to an EV, it's the perfect candidate in lots of ways - the rwd rear engine makes a motor install easy, there's plenty of unconventional spaces to stash batteries in without ruining practicality, there's plenty of room for improving the performance over standard, and redistributing the weight throughout the car will improve the handling, so unlike many other potential EV conversions which ruin their base vehicle, the bug will be a much better drive as an EV than it was before.
_________________
"I looked for silver linings, But you're rotten to the core" - Devo: Gut Feeling (they must have seen my Super)

[Kramer79]

I have an older conversation “kit” if anyone is interested. I don’t know a ton about it but a heavy advanced dc motor and some dc controllers a bunch of wires etc… if anyone is interested let me know