Thanks for the replies. This topic is interesting to me for some reason :) I'm always curious about systems like this. The combinations of boat, motor, prop, engine height, pitch, etc. There are enough variables to make it complicated.
From my research online it sounds like if I can get my boat set up just right it should do in the neighborhood of 74mph. I have no interest in speed for regular fishing but on tournament day if I can get another 2 or 3mph out of it then I'm interested.
Wish I had the time to go up to Shasta for a week and try different props from Phils and stuff. I hate wasting fishing time to jack around with boat stuff but I want my boat dialed in to the max because that brings enjoyment at the lake too. Nothing better than having a clean mind knowing that your equipment is just right!