[macojoe]

you would think a good shop could have steered you in the direction of the right size prop!!

When mine was a I/O (165 hp Chevy 250) I had a 15 1/4 X 15

when I switched to O/B I was told to go to a 17 pitch. It pushed the boat fine but I still felt that it was wrong. I bought another 15 1/4 X 15 and i love the all around performance.

Of coarse this is what worked for me. and you may like something different.

A good prop shop can tell you what you need over the phone to with in one size.
They just need boat length, weight, make, and HP. My shop even let me take a prop try it and said as long as I didn't hit anything i could swap it.

:-*