Re: prop advice
One rule of thumb is to drop roughly 2-300rpm an extra inch of pitch, and 100 rpm for each extra quarter inch of diameter. Plus an ss prop will usually spin 100-200 rpm slower than an identical pitch/diameter aluminum/composite. Exact impacts vary depending on the hull, motor, and different prop designs. There's a little bit of guessing involved.<br /><br />You sound like you are way overpropped, but before you assume so, I would doublecheck your tach is accurate and on the right pole setting and also confirm that 5200 rpm is the recommended wide open throttle (wot) for that motor (it should be stated a range not a specific rpm -- check your manual or with your dealer -- you want the motor to top out near the top of the recommended range). Does the motor sound like it's lugging? Is the motor trimmed properly to the transom? If you really are running at 4600rpm then you want to drop at least 2 inches of pitch and maybe 3. You will gain hole shot and control and probably maintain or come close to your existing speed.<br /><br />If you are out as much as you say then I would try to find a prop dealer who will let you try a test prop -- there are so many variables that you are unlikely to get it just right on your first guess starting from so far out. Also, don't wait to fix this, you will carbon up your motor running it at low revs like that,.
