I am trying a mercury maximus on my Daytona and have a question on the vent holes. Are these just for through hub exhaust. Do you leave them plugged for through transom exhaust. Is there any benefit to opening them. I might need a little prop slip to get the motor in its torque range so some slip before planing would be OK.

Vent holes are usually reserved for outboard motor applications. It won't hurt to take out the vent plugs, they really don't do much after the boat is on plane. If you don't need them I would leave them plugged as there are some occasions when they may be a problem, especially at minimum planning speeds.

Matt

There was a thread at one time on here about the vent holes. I wish I could have you read that.

The vent holes do nothing once the boat bows over and is on plane. The water across the tube closes them. Once you have run the prop and have some good data, we can discuss the options to the Maximus. This propeller has as many or more options to adjustments than any propeller on the market. In other words, inducing slip can be done in other ways.