[NoBones]

Length of boat ?, Horsepower and make of motor ?, Trim tabs
yes or no ?, Pitch and size of prop ?, All of these factors play into where you want to mount the engine....
My 20 SF is 2 inches trimmed out to the bottom of the keel.
Have 24 inch Bennett's, with a 21 inch Laser II prop.
Tops out above 61mph with half tank of fuel (80 gal. top)
Keep in mind my 200HP Merc has been gone through from top to bottom. Boysen reeds, shaved heads, ported and polished intakes etc, etc. Let us know, we can take it from there.
See ya, Ken