Top Motoring speed for Oceanis 390

[rongroth]

Would like some ideas of how fast people can motor at what RPM. I have a Volvopenta 2003T 43 hp built in 1991 with a Autoprop

 

[NiceBeny]

Ron I didn't mention I have a fixed three blade prop and with a clean bottom it moves at a good pace. Thanks for your help

 

[zzmeyer]

In general, you should be able to motor at 1.2 times the square root of waterline length. At hull speed you use too much fuel. If your boat is the 39 that has a waterline length of 33.25 feet then 6.9 knots in flatish seas is a good rule of thumb. I believe the maximum rpm is 3200. Run your engine at full speed to make sure you get 3200. If not, you are either over propped or underpropped. You should get the 6.9 knots at about 80% or 2600 rpm