performance potential w/ 6s lipo?

[BrianG]

When you go with higher voltage, you can choose a motor with a lower kv/higher wind count, which will help runtime. Also, less current is used to get X amount of power so any current losses are less as well.

You generally shoot for 35k rpm as the max motor rpm. To pick a suitable motor, just take 35000 and divide by the voltage. That will give you the motor kv to get. Then, just find a motor with a kv in that range.

Runtime increases by going to 8Ah from 5Ah depends on what you are getting now. Assuming you are using the same motor and gearing and voltage: If you get say, 30 minutes on the 5Ah, 8Ah will give you 48 minutes theoretically.