ORIGINAL: Matt Kirsch
johnnyjetprop,
The AXi 2820/10 is rated for up to 10 NiCd or NiMH cells, or 3S LiPoly. 4S LiPoly and an 11x9 prop would be overloading the motor severely, unless you know something about their ability. Remember, Motocalc does not handle outrunner motors very well. The numbers may look okay, but with Motocalc, once a certain threshold is reached on an outrunner, the current drawn stops increasing, the motor gets very hot, and the efficiency goes way down.
An AXi 2820/12 would be appropriate for a 4S LiPoly pack.
You are correct Matt. The 2820 is 10-14 cells and 35a max. I have seen them handle 40a for 15 sec burst, but I have also seen them demag at 45a.