I was wandering if anyone could advise me on a set of new props. My boat is a 27' stingray with twin 350 mags and alpha 1 drives, both drives are right hand and have 3 blades 14 1/2 19 pitch, I would like to use these as spares and get new 4 or 5 blades props.With the 19 pitch the rpm @wot is 5100. any help would be great .
thanks Rob

What model 3 blade props are they?

I wouldn't recommend a performance type of 5 blade prop on the Alpha drive. Besides that there are no performance 5 blade props with a low enough pitch for your application.
You are going to be hard pressed to find a 4 blade performance prop with a pitch below 20.
What year is your boat?
What speed do you see @WOT?

Matt

Actually, there are 2 offerings in 4 blades from Mercury Marine that we carry. One is the Ven-Sura in 17-23 pitch.

Also there is the performance propeller we love called the Revolution 4 in pitches ranging from 15-25 inches.