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I just got a prop from a friend and it has several grommet fittings on the drive side of the prop. Currently they are not in, but he said that you ocan insert these grommets and it changes the perofrmance.
Can anyone explain what these are for, how they help, and what is the best way to use them. If I recall, it is a 19 blade Mirage. I do have the silent choice set up for the exhaust, so when I am in performance mode, no exhaust is exiting the prop.
Any and all feedback welcome. 21' Eliminator Daycruiser, 1982, 350 smallblock @ 415 hp.
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If you are talking about holes at the base of the blades just to the back side of the blade, they are used to get air (from you exhaust) to the prop. It will make the prop slip at slow speeds. It will help a heavy boat get on plane quicker, then as speed picks up the wash over the prop kinda makes em quit working. But you exhaust has to go thru the prop to work.
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If you are talking about holes at the base of the blades just to the back side of the blade, they are used to get air (from you exhaust) to the prop. It will make the prop slip at slow speeds. It will help a heavy boat get on plane quicker, then as speed picks up the wash over the prop kinda makes em quit working. But you exhaust has to go thru the prop to work.
What he said. They are designed to let exhaust intentionally cavitate the blades. Different size holes in the various plugs allow different amounts of exhaust out and more or less slip.
BUT, it don't make a damn bit of difference if your exhaust is thru-transom. :wink: