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View Full Version : installing bennett m80 trim tabs on sweet 16



cb taylor
05-15-2011, 03:31 PM
Has anyone had any experience. Did the m80 style with upside down fins work ok?

Just Say N20
05-15-2011, 09:33 PM
This style tab has been installed on many Donzi classics.

While the horizontal mounting of them shown in my signature picture is different than the typical parallel to the bottom installation, I have seen several classics with this style tab.

The original Bennett tabs had a flat surface. I haven't read much about these, but perhaps they figured out tis provides better control by not allowing the water pushed by the tabs to spill out the side. Who knows?

hdsadey
05-16-2011, 08:56 AM
Why are the tabs mounted parallel to the water line rather than the hull line? I see no advantage to this. While underway they are useless, correct? My 16 came factory with m80 tabs and they are mounted along the back all the way at the bottom.

Just Say N20
05-18-2011, 07:13 AM
I mounted them this way to try something different. The 16 is small enough that it reacts very quickly to tab trim changes. By mounting them horizontally I thought it would allow more gradual changes as progressively more of the tab came in contact with the water as the tabs were lowered.
At low speeds, the water rises very close to the transom, so a large part of the tab should be in the water if the tabs are down. At high speeds not much tab correction should be needed.

I mounted them a little higher to make sure they wouldn't be dragging in the water when up all the way.

So, I hope they work as expected. The boat will be in the water by
Memorial Day weekend, so I will know shortly. :)