[trit21]

You should turn over rated RPM to ensure long life from your engines. IF your MAX rpm is 2700, you should be able to turn 2800 + fully loaded as you use the boat, not a light load. If you max is 3000, then you should be able to turn 3100+. If you visit boatdiesel.com you will find many (including me) that agree with these numbers. Go to SBMAR.com (Tony Athens website) and look at the many many article and tips he has on the 6b engines and how to make them last a long time. My boat is a 2000 3500 with 370 6BTA's. She turns right at 3100 at WOT fully loaded. Cruise is 2400-2600 RPM at 23.5-25knots. My props are 23x28 and when I purchased the boat I removed 1"of pitch to achieve those number, especiallly the 3100 full loaded spec.

Tom