When cruising with my merc 5.0 alpha 1 on my 22 ft Sea Ray EC, I
occasionally experience what I think is cavitation when encountering rough
or choppy water at speeds around 35 mph. To get out of this condition,
adjusting the trim has little effect and sometimes it is necessary to come
off plane. I know there are some devises that can be attached to the
outdrive to help with this. Does anyone have any experience with this that
could perhaps recommend a solution?

When I refer to cavitation, the condition causes an increase in RPM and a
decrease in speed and is caused by the prop is not making proper contact
with the water, due to too much air around it.