RE: New Sig P-51B 90-100 size??
I have used the Power 60 in planes up to 10 lbs. with good sucess. I currently have one in my 10 lb. Tucano and it's great. I am getting 1400 watts peak using a 16-12 prop. I am pushing the motor a little, but it should be fine as long as I don't hold full throttle for too long. Otherwise a 16-10 prop is just perfect with a 6S pack. I get 1200 watts which is plenty for an 8 lb. plane like the P51B. It won't be a speed demon, but it will have plenty of power.
Jeff