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FJB20
06-29-2002, 08:22 PM
Read a Little on Alpha Drive Gear Ratios
1.47-Primary 1.81-Optional 1.62-High Altitude
Which is Faster and Why -- if My Boat is in So. Jersey - Why Do I Have a High Altitude 1.62R
Also Have Vengeance 21P Prop Thanx!!!!!!!!

FJB20
07-04-2002, 09:33 PM
1.62R means What???

Rootsy
07-04-2002, 10:05 PM
1.62 means.... that the motor spins 1.62 revolutions for every revolution of the prop shaft... the R means that it is right hand (standard) rotation.

Last Tango
07-05-2002, 02:51 PM
Three possiblities for the gear ratio - (1) the boat was originally built for a customer who did not expect to take delivery at sea level, or (2)the outdrive on your boat was replaced at some time and nobody paid attention to the gear ratio, or (3), the engine in your boat needs a higher gear ratio to spin the prop at the desired RPM of the engine. Mercury makes only 3 gear ratios to meet a whole ton of different demands. Hopefully your ratio works for you.