There is a direct relationship between the pitch and your engine RPM. Reducing pitch increases engine RPM, allowing the engine to develop more hp and torque. The starting point is your current prop. I forget exactly what prop your boat came with, it could be one of several. Also, I need to know if your shaft is splined or uses a keyway. The two are not compatible. Your hull has used up to a 20" pitch prop, depending upon year and transmission.
Getting more hole shot almost always will use more gas during riding.