OI33 prop size

[paul17696]

what size props and what is the pitch on an OI33 with a 50hp perkins. i believe the reduction is 1,5 on the gear

 

[Ross]

The calculator on boatdiesel.com

Says Three blades 13.5 diax7.5 pitch increasing transmission ratio will improve prop efficiency. I used 29 feet lwl and 14000 pounds displacement.

 

[Frank Saul]

OI33 prop

13.5 Dia sound a bit small If you have a borg waner you may have a 2.56:1 gearI have a 18X15 on mine nowBut I am changing morors to a Vetus m4.17And I need to reprop not only because of the lower HP but the rotation is the opposite.Would you mind giving this a try in the calculatorGear reduction 2.63:1Displacement 16000LWL 27.542HPThaks for your helpFrank