Jerry it is worth taking a look at the website link to "performance" and view
the annual results of the Ottawa comps. Most on record use 60x72 and run close
to 3000rpm. IMO if this prop were reduced to say 56"dia and run at 32-3300rpm
the performance would be faster.ie increase rpm by reducing the diameter (to
a certain limit). I don't think we have found the limit yet. I have chosen a
60x72 Sterba but will cut it down to achieve redline rpm at WOT level
flight,but I suspect you could go as high as 74" pitch with a reduced
diameter.I think there is more potential airspeed to be found.
Peter