I took my v-20 cc out for a cruise the other night with 5 adults and my 3 year old daughter. At WOT the motor reached just under 5200 rpm's and gps said we were going 37 mph. The motor is a 92 150 evinrude and I think the rpm's should be around 5600-5800.My prop is 14.5 by 19 and was thinking...