Hi,<br /><br />I have a Peterborough 18.5' X 7.5'1989 whith a mercruiser 4.3/ Alpha One. 185Hp<br /><br />I ran 48Mph / 4700 rpm<br /><br />I have a Aluminum 3 blade 20 pitch on it, for the next season i will buy a steinless prop.<br /><br />What is the best pich to choose to hit the 50 Mph.<br /><br />Thank for our help.<br /><br />P.s. i am a french Canadian, don't hit me for my bad english 