Logo
FULL SITE MENU

Gear Ratio

Friz Freleng

Friz Freleng

Member
I am trying to determine the best prop for my boat. It is a "71 LM318 with a Volvo 250 or 270 sterndrive. Can anyone tell me the gear ratio? I have found a prop size calculator from Vic Prop in Canada and gear ratio is part of the calculation. I have a 200 manual and it says the ratio is 1.59:1 or 1.85:1. When I plug those numbers into the calculator I come up with prop much much larger than the beat up 3 blade one that came with the boat. The calculator says something on the order of 18.5 X 19.8!
 
You don't have all the freedom for many prop calculators due to the drive leg so take them with a grain of salt.

Volvo used to stamp the housing with the gear set's ratio - think it was under the zinc....Rick should be able to give you the specific location
 
Back
Top