[JohnS]

Dinger,
Sounds to me like your motor is set too low. When you are running, the cavitation plate on the motor should, ideally, run even with the water line as you are running. It is ok to be up a little more but, you may wind up with some cavitation. Also, Mirage props have the holes in them to aerate the prop. The older props did not but, I know the newer ones do. Personally, the props work much better with the plugs removed. You can remove one at a time and see how it works for you, each hull is different. I have a 225 Optimax running on my 23 Concept with a Mirage 21 with all the plugs removed. I had the motor running all the way up but dropped it down one set of holes due to cavitation in some slower following seas. Basically, unless I was hauling butt, it was cavitating. When I dropped it one set of holes, I lost about 4mph but the cavitation went away. Granted, my boat is lighter then yours, about 2600 dry but, you should be getting more from that Opti than you are.

John