ya go with what he said 5.1x4.5 my be to much I have never ran the 2w-20 just the 2w
I tend to go bigger on the props and batt's being i am just over 5000 feet and it's hot dry air
I run hot set up's so I also can't fly when the temp is over 70f
if you have a watt meter play with that and some props and watch the amp's to the motor and if you go over the amp's rated for the motor watch the heat and remember to throttle manage