when the motor is trimmed all the way down the cav. plate should be flush or up to 1 to 1.5 inches above the keel (the lowet partof the hull or the rib running down the center)
The plate above the prop on an I/O or Outboard is an antiventilation plate. Calling it an anticavitation plate is incorrect.
Cavitation is different than ventilation. Ventilation is when air gets to the prop. The AV plate stops that ventilation.
Cavitation is caused by low pressure or vacuum behind the trailing edge of the prop. Ofter, it erodes the metal of the prop, due to the boiling of the water and other forces..
ok so i moved the motor up a bit to get the "plate" at a better level. Now exactly what will this do for me? will the effects be very noticable or not?
Note: previously the antiventilation plate was about 1.5 inches below the keel of the boat when trimmed down. now it is about 1 inch above the keel.