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Originally Posted by Serum
not necessarily. You need to find the sweet spot.
My 7XL stays rather cool on 14 cells. meaning it's running rather efficient. if you put your epa on 70 percent, you will have good runtime, and you'll be able to drive fast if you set it to 100 percent. Something to think about.
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That's a good idea w/ the EPA. Would give alot of flexibility of different tracks or conditions. Do the efficiencies really change that much on the XL motors just by going up/down a turn, given the same number of cells? I haven't seen their charts.
Playing with the motor calculator on the Neu motors website, when comparing a 2700 kv (1D), a 2200 kv (1Y) and a 1700kv (2.5D) 1515 motor, all on 14 cells, the efficiencies run:
91.9%, 93.3%, and 92.1%.
The current draw runs 111A, 75A, and 57A.
Motor RPMs; 46K, 38K, and 30K.
I understand this is just a calculator and there a huge number of other things that go into this, but perhaps I'm missing something?
Generally the advice above is also given to 1/10 scale systems (say all running 6 cells or 2s.) If you want the the fastest, go a low turn, say a 3.5R or 7700, but heat and runtime will suffer. If you want more runtime and don't need lots of power, go with a 6.5R or a 5700. If you go too low, I would think the extra current load would overshadow any changes in eff, if you are talking within a narrow range of turns.