I recently bought a 1987 Rinker 250 with Mercruiser Alpha One 260 (5.7
liter). There are no markings on the existing prop, but it appears to
be almost a flat prop - no cupping. The performance is poor, but WOT
is about 5500 RPM. Looking for suggestions for a new proip, or at
least a starting point. I don't want to spend thousands of dollars to
dial it in.