Hi all i'm not sure where I should post this. I have a 2010 Sylvan Mirage Tri Toon with a 150 Merc Verado It came with a 14.5 X 19 pitch Alum. prop and if i trim the motor up at all it will cavitate. If i leave the motor trimmed all the way down it's ok and i am running at 30 mph and 5000 rpm...