Just Picked Up A Set Of SSM 5 Blade Merc Cleavers For My Flat Bottom Top Gun. Ill Be Spinning Them In As I Need More Stern Lift But How Much Lift Are We Talking Here? I've Always Run 4 Blades, Just Trying to Get An Idea Of How Much Different Its Going to Be And What To Expect...ps they are 15* rake..

Spinning "IN" provides bow lift, not stern lift. If you feel you need stern lift, 15* rake 5 blades will add some over the 4 blades, assuming they are also 15* rake, which most merc 4 blades were.

In my experiance, a straight bottom gun will like bow lift. Turnin props in, higher rake, smaller diameter, minimal blades, etc if its top speed you seek. Lots of variables though. Best option is to try different props and take notes.