We have a 2004 Hunter 33 with a Yanmar 3YM30. Last year we had a two blade prop and were able to cruise at 3200 RPM and acheive in excess of 7 knots while motoring in calm seas. Then the wind picked up and the engine overheated and we discovered that Yanmar had put a seawater belt on which was an inch too long and that it was slipping at higher rpms. After the belt was changed, because of frequent high winds, we did not ever get an accurate take on this statistic. Now we have a 3 blade prop. Although we still have high winds, we can't seem to achieve more than 6.5 knots and it is overheating at 3,000 rpm. The tach reads in excess of 4000 with max throttle. The manual says that we should be able to run at 3600-3800(max) for 30 minites and 3400 rpm for 9 out of 10 hours. For you that have this same boat and engine, we will appreciate information about the performance of your boat.Thanks,John & Rachel EhrichtBaton Rouge, LA