I've picked up a used 4.55m tinny which is equipped with a Honda 50hp four stroke outboard.

Quite sure the outboard is mounted too low on the transom as the anti-ventilation plate - which sometimes referred to as a cav or cavitation plate - is 1/2" below the keel. When on the plane the anti-ventilation is well buried below the surface of the water. I feel this is slowing the boat down with extra drag from the leg. Normally I would setup outboards to have the anti-ventilation plate to be just skimming the surface when at cruising speed on the plane.

However, the Honda BF50D has a third cooling water inlet. There are the usual two inlets either side of the skeg and an additional one on the lower side of the ventilation plate. I'm concerned about sucking air into that third pickup if the anti-ventilation plate is skimming the surface.

Is anyone running a Honda four stroke and can reassure me they run fine at this height?