Gearratio of an 1983 johnson 70horse

[Pete]

hey,
i was just wondering what the gear ratio of a 1983 70 horsepower johnson seahorse is. where can i find this info? or if someone knows could they please post?

Pete

[Laker]

The 70 hp and 20 inch 75hp is 12:29 or .414
The 15 inch shaft 75 hp is 15:28 or .536