ate 800 stringer drive -mechanical shift-gear ratios?

[Boat Doctor1]

I have a omc od with upper drive bad it is a ford v8 302 engine (omc) and a 21-16 gear ratio- i have located a upper that is a ratio of 21--20(3.8l) and another with a ratio of 21--19 (4.3 l) What difference will either actually make??if installed inplace of the v8(21-16) ?? the 21-20 is a almost a 1-1 ratio & maybe the 21-19 maybe better?? yet couldnt I just change the prop for ratio differences? or??

 

[Howard Sterndrive]

start with the basics... alt belt slipping? battery terminals and ground connections clean and tight. visual check of connections at ignition switch and other easily accessible spots.

 

[Boat Doctor1]

hi Howard-thinking you answered the wrong post??