GOOD NEWS. . . . The PICTURE UPLOAD FUNCTION IS WORKING !!! The tech folks at the parent company have been able to remedy the issue. You can upload pictures once again. Thank you for your patience.
Best you are going to get are some guesses because you cannot provide any performance data. The more details you can give, the better the guesses will be.
HP of engine
make model of boat
weight
hull type
gear ratio of drive
etc...