[Bigshrimpin]

I started out messing around with props @ 43/44mph on a MA with a 1981 Merc v225 w/wh-22 carbs. I tried tons of different props (ignoring good advice from everyone who's done this before) and finally broke 50mph this weekend using a Mirage 19 plus.

1. Weight and Wind Resistance make a huge difference. Minimize both.
2. Raising the motor also will give you extra speed especially if the engine is low. Try raising the engine a few holes or get a jackplate.