Right propeller pitch choice

[Mghandour]

Hi all ,
I have a maxum 2700 se model 2004 , I just changed my engine to mercuiser 350 mag MPI with 300 HP and a Bravo III sterndrive ,
I was told i Have to change the propellers to acheive the required speed , my current propeller is 22 . And i was advised to buy 24 or 26 .
I need your valuable advice about the right choice for the new propellers , thank you in advance