adding a difuser ring
 

Thinking of adding a difuser ring to my Hydro QIV help w/ planning. I understand this may cost 50-100 RPMs. I assume this would mean its slightly slower on the top. Anyone add a difuser & lose MPH @ WOT. Just wondering what to expect.

Adding a diffuser ring increases stern lift and drag. In some cases the added stern lift can improve over all performance and in other cases the drag and stern lift reduce performance numbers. It depends on the boat you are working with and what its personality is.

Brett

The boat runs pretty lose the way it is. I certainly don't want more stern lift. Could you trim the blades to compensate for the added lift? Trying to decide whether to modify this prop or abandon it & go another direction.

Actually we wouldn't trim the blades but rather bend the tips and roll them to a certain height.

Brett