Drive ratios for small blocks/Alpha drives.
 

I'm replacing the Alpha One on my boat this season with a new unit. I've talked to some folks that said that an old trick for higher-rpm engines was to setup the drive with a lower gear ratio... take a V8 drive (1.5) and replace with a six-cylinder drive (1.65 or lower)... I have the ability to spin about 5900 RPM. I think I could get a lot more speed out of the boat with a change to the 1.65 ratio and a 25P prop (of course I would have to test for the right prop).

Any suggestions?