jucava, I'm not sure about the three blade prop, but I DO have a (prop) brand recommendation...

I'm not usually one of those guys thay says "This prop is the best" or "that prop is better", but I have to say that I have found the Graupner props absolutely RULE the 4-stroke engine catagory. Check out a 13.5 x 8 two blade, or a 12 x 8 or 12.5 x 7 three blade.

Here's a link:

http://www.hobby-lobby.com/grprop.htm