finding the right prop

[Fr. Frank]

Pay close attention to the mounting height of your motor, If you're still ventilating (It is NOT "cavitating") at any motor trim angle other than pretty well trimmed down, I would suspect one of three causes:

1: motor mounted too high (this would also explain slow time to plane with accompanying cavitation upon hard acceleration from a standstill)
2. insufficient cupping on the trailing edge of the propeller blades OR full cupping not extending to the middle of the blade tips
3. A wake obstruction on the hull ahead of the propeller/lower unit such as a through-hull fitting or transducer.

Cavitation is air bubbles forming on the trailing side of the propeller that is caused by pressure differential, and results in reduced "bite" and reduced thrust.

Ventilation is air bubbles being pulled down from the water's surface to the trailing edge of the propeller. The whole purpose of cupping a propeller is to minimize ventilation, and yet still allow a propeller to run right at the water's surface, minimizing drag and friction.