The Turnigy 4000 and 5000 packs are 50mm wide and are a tighter fit. 40C is OVERKILL and wires are way too thick for what you are doing. I prefer the narrower 3600 versions lots better.
I just placed an order to HC for 2x 4s 3600mah 30c, 2x 2s 4000mah 30c and 2x 2s 4000mah 40c. Hopefully this is a good starting point for this project. I do hope to get some testing in with the 2s 4500mah 30c and 2s 5000mah 30 hardcases packs I already have.
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