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dubkatz
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05.20.2008, 05:58 PM

Quote:
Originally Posted by sleebus.jones View Post
Not really. It's pretty thin stainless, so it's not that heavy. I meant to throw it on my postage scale, but forgot. Aluminum really wasn't an option because to get enough strength, it would have been too thick to fit in that area.



Yes, those are A123's. The voltage drop isn't that surprising when you suck 100A out of a cell that's rated for 70A. The time scale is in seconds, so it recovers in under half a second. Actually the drop is from the front wheels coming off of the ground, the second spike is when they hit. The pack is a nominal 19.8v pack, so yeah the voltage drop is around 3v, but as fast as it is, I'm not too worried. I was running road rage tires on concrete, and just burying the throttle for the launch, so what you're seeing is a worst-case scenario. Something like crimefighters (or panthers) on a dirt track will spike less.

Yes, A 6S2P would help a lot with voltage drop, but I really don't want to pay the weight penalty. I also seem to have one cell that's a bit wonky, so that may be contributing to the drop a bit. It's pulling in closer with every cycle, but I think I may have to end up replacing it. It peaks way faster than the other cells, so something may be goofed up with it.

I've got no information on runtime, because with the testing/etc I've yet to really get out and run it. I'm pretty sure I'm in the 15 minute range. The motor in it is a 10XL, it barely gets warm. I've temped it at around 115 degrees.

I've got an embarrassingly bad video of it here:

http://www.youtube.com/watch?v=PZzHn7Pb1-M
I have def seen worse video's
thats good runtime. im sure the low gearing, low kv motor, and hv all plays a big roll in that. Thats def. a nice setup esp. for racing. lightweight, short gearing. im sure youl realy suprise a few nitros guys
   
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