I have a nice light simple stick, and with an out runner brush-less motor and an 8 cell pack I get about 9 minutes duration with a 9x7 gws prop, now if I change the prop to a faster turning 5x4 the white push on kind that are very efficient and very light, can I still get the power and more speed as if it were a flying wing type plane and yet have at least 7-9 minutes of flying time?