See posts 16-18 of link below..
http://www.bbcboards.net/showthread.php?t=1007326
Still haven't gotten to run the 30 pitch promax wide open yet..It will run over 85 with ease.
Here are some numbers with a 28 Max 5 on my Basport with the 250R. It's a free phone app called Drag Racer. It's not the best for boats since starting requires the boat to be dead still. (Gets tricky with a little breeze) and definitely makes for a slower time vs a rolling start. Only made two passes as I had my dog with me. I know it will do better with some testing to trim correctly. Next time I'll make several runs and also do some to 85. I think this prop could run 87-88 @ 6200 with some coaxing.
drag race (2).jpg