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Discussion Starter · #1 ·
Going to use model s large rear drive unit and probably an ev west controller. Getting the suspension up to date and some more meat on the ground. Waiting on fenders. Kinda hung up on the battery choices at the moment.
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Discussion Starter · #5 ·
That's a lot of rubber, and it looks like a solid car to work with. :)


By "up to date", do you mean "completely replaced with something unrelated to the Beetle", or just "new shocks and bushings", or something in between? I see CV joints (a good start ;)), but while detail is hard to see what is there looks like original Super Beetle semi-trailing arms (and struts in the front).
Sticking with vw parts. Just literally replacing everything. Urethane bushings, big front and rear sway bars etc. also added front and rear truss bars. the McPherson strut set up seems to work really well on these.
 

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Discussion Starter · #15 ·
Absolutely... although this thing won't lift the front tires (and the high school Beetle had a 2.0L VW 4-cylinder boxer). The point is just that a non-rusty Beetle won't fold up just because you put in a lot of power and sticky rear tires. Be careful about structure, yes, but this isn't new territory or unworkable.

The handling of the resulting vehicle is going to be questionable, if only because the major masses (motor and battery) are beyond the axles. It's essentially the opposite of the optimal vehicle configuration, which is mid-engined.
What are your thoughts on a Tesla type pack in the floor? The seats are up on 4鈥 pedestals as it is. Cut out the tunnel and box everything in.
 

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Discussion Starter · #24 ·
Ok purchased the ldu today. Also got the axles, gv200 solenoids and the pyro fuse. Anything else I should grab from the donor car? Gas pedal was already gone. Any one using the t2-c controller from ev west?
 

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Discussion Starter · #29 ·
Wow the negativity is strong in this group. I said from the beginning I鈥檓 building a toy not an electric 1000 mile range yugo with a top speed of 35 to carry the kids to kindergarten. I鈥檓 done with that phase. Thought y鈥檃ll would appreciate something different. I definitely walk to different beat. guess I鈥檓 on my own here.
 

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Discussion Starter · #36 ·
Among non-competition automotive applications, the place where high power output relative to battery size (or energy capacity) is needed is in hybrids: they need to put out enough power to drive the vehicle, despite being small.

When the energy capacity required is really small (a classic hybrid that can only move a few blocks on the battery alone) nickel metal-hydride (NiMH) is still viable - Toyota still uses it quite successfully.

When more energy is required, for plug-in hybrids (and the logic would apply to short-range EVs), lithium-ion is used, but in specific electrode chemistries for power density (at the expense of energy density) and with sufficient cooling that it survives. That is a reason for the popularity of Chevrolet Volt batteries in relatively high-performance DIY conversions: in addition to being plentiful, and having been around for a while, a 16 kWh Volt battery can put out 120 kW for at least 10 seconds at a time even by GM's conservative ratings. The LG Chem modules built for the Chrysler Pacifica have been popular as well: plug-in hybrid power capability, and while the Pacifica Hybrid is rare compared to the Volt, the modules (new) were sold by various suppliers. There are other plug-in hybrids, although none are as common as the Volt and none of their modules are as available as the Pacifica modules were.

When the supply of Pacifica modules was cut off, EV West apparently went looking for something else they can buy and found the JH3 modules. They have apparently found them suitable at high C-rates; my concern is that this is not endorsed by LG Chem and this isn't even the ideal choice from among the ESS product line for high discharge rate. Maybe they'll work at repeated sustained high discharge rate, but I'll bet EV West won't warranty them for that.


The other solution is simply to use a big battery. Any cell technology is limited in its discharge rate relative to its capacity, so if you double the battery size you get double the power capability, even though you don't need the energy and don't want the weight or bulk. It's not a coincidence that when two Tesla models have the same motors, if one has higher rated power it also has a bigger battery. You might hope for a Model 3 Performance with the less expensive and lighter standard-size battery, but they know that won't work so they won't sell it to you (and they have more mercenary reasons as well, of course;)).


There have also been companies offering high-power cells for drag racing applications. Maybe they are still operating; they're certainly not relevant to reasonable street-driven EVs.
Thank you this Brian. As stated this is going to be a toy. I鈥檓 just looking for maximum performance and I鈥檒l adjust the range to suit. I can鈥檛 go crazy and spend $25k on batteries but I鈥檓 not afraid to buy what I need to make it what I want it to be. Obviously I won鈥檛 be able to put the torque from this Tesla sport ldu to the ground right off the line and I鈥檓 not trying. Nothing would make me happier than to need new rear tires after a long weekend. 馃榾 I鈥檓 really here because I just don鈥檛 know what direction to go. I like the idea of liquid cooling but that comes with a cost mostly added weight that being said I also want to be able to make the 20 mile drive into town mostly open road 55mph, have some fun and come home. I certainly could charge in town if needed. Thanks
 
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