Maximizing outboard motor preformance

try running the motor at different angles of attack. Just play with the switch that lowers the motor while your running flat out. See if theres any diiference at a higher angle of attack.
Is your motor a long drive? We use a Merc 115 hp on a small T Bird and it planes out and runs the boat at a top spped of about 35 knots . (We cruise at maybe 25).

Does your engine fould much? Is your mix right? can you use hotter plugs?
Id start with the angle of attack , maybe that or setting the engine lower. Im n ot sure about the engine settings cause I bought my little T bird as a fixer upper project and the engine mount plates were already on.