[tsubaki]

I'm running a stainless 14x19 but only get up to 5000rpms at 44mph wide open. A 14.8x17 aluminum did the same numbers. I'm also lightly loaded and only a 40 gallon fuel capability.
Depends on how you tend to load the boat fuel and bow monkey wise as to what might be best.
A load with a couple of guys (non MJ size), 60 gallons of fuel, their food, drink and fishing stuff might do good with a 17 pitch stainless.
Now if you got a couple or few MJ's and a lot of stuff, you might need to go down to a 15 pitch.
I'm still dragging my feet as to getting mine tuned in correctly, I know I need a smaller pitch.
That motor did 5000rpms and 42 mph with the 14x19ss or 14.8x17al in my situation.