just for clarification. I am looking to get some more speed out out of my 21 ft scarab where I have a fresh 454 installed and have been doing some research on trying a " shorty". I see gear ratios listed with them. I thought gearing was in the upper and on the prop? Just was wondering what gearing I should be looking at and any suggestions on how high up I should go.

thanks

Your gear ratio is calculated between the combination of the upper and lower gears...you have to figure out how many teeth are on your lower unit gears to get the rite gear ratio..

I was told that all Bravo uppers were the same, and that the gear ratio is determined by the lower. Unlike the Alpha,which is determined in the upper.
Can anyone else comment ????

Older B1's were determined in the upper.. Since the XR the lower gears can determine the ratio.. So it ends up as a combination of the two...

Hope that helps.
Dick