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David Hartmann
04-28-2006, 10:05 PM
I try not to start new threads, but, I did spend sevearl hours searching online before aasking this question.

Where do Trim Tabs go.

1) How far from center or edge?

2) how far above bottom of boat?

3) What angle to the hull?

1) I have heard that you want the far away from the drive so that they are not impacting flow to the prop but I would not think the outer edge is best?

2) .25 inch above or 1 inch above?

3) I see on new boats they are often parralel to the water as opposed to parralel to the bottom of the boat.

I am installing 12x12 tabs on a 19' St Tropez (Donzi).

I am sure a lot of would benfit from other experiance. I appreaciate any help Thanks.

MOP
04-29-2006, 06:54 AM
You will get a few answers, I have mine 8" in and 1/2" above the hull at the hinge and 1-1/4" up from that at the trailing edges so they run clean at speed.

Phil

DickB
04-29-2006, 10:23 AM
Good information on the Bennett site:
http://www.bennetttrimtabs.com/online.html

MOP
04-29-2006, 12:06 PM
Problem is if you mount tabs to the Bennet spec you will loose performance and a heck of a lot more than you think. If you email Tom at Bennet he will tell you the mounting instruction are for the average boat.

Phil

MOP
04-29-2006, 12:16 PM
Though a different type/style here is a very good shot of tabs mounted for optium performance. Courtesy of one of the good Southern Boys!

http://www.donzi.net/forums/attachment.php?attachmentid=20268&d=1146102791

David Hartmann
05-01-2006, 12:26 PM
Though a different type/style here is a very good shot of tabs mounted for optium performance. Courtesy of one of the good Southern Boys!

http://www.donzi.net/forums/attachment.php?attachmentid=20268&d=1146102791

This looks pretty normal
They appear to be about .75" - 1" up and about 6" - 8" from outside of hull.

They are parralell to the hull. Does anyone have any thoughts on installing them parralel to the horizen. Or somewhere in between? It would seem that this way they would have a lot of control at low speed and less control when the boat is on full plane.

glashole
05-01-2006, 12:31 PM
they should be installed parallel to the hull of the boat and up enough so as to not drag when they are fully up to get the maximum effect

The idea of them is to actually become part of the running surface of the boat when in use.

I can't see any purpose for them when not on plane

regards

Shea

Ed Donnelly
05-01-2006, 11:35 PM
Can't tell you the proper specs,but,I can show you how NOT to install them.
These were installed by a hot shot high performance marina for me...Ed

BRIAN73
05-02-2006, 03:20 PM
Dave,

Did you end up going with hydraulic or electric????


Inquiring minds need to know

David Hartmann
05-02-2006, 11:10 PM
Can't tell you the proper specs,but,I can show you how NOT to install them.
These were installed by a hot shot high performance marina for me...Ed

I am confused why do you say this is how not to install them? do they perform badly. it looks like they are installed the way most people are suggesting. They are arriving soon I am looking for help and gettting nervous.

David

David Hartmann
05-02-2006, 11:24 PM
Dave,
Did you end up going with hydraulic or electric????
Inquiring minds need to know

If I answer this it is going to derail the thread as to wich tabs are the best.

I answered in a private message. I went with the same as on your boat. Do you have any thoughts on placement. I have to be drilling holes next week.

Ed Donnelly
05-03-2006, 12:52 AM
David;The tabs were mounted too low and are at different angles to each other(use the horizontal stripe as a reference)

Mr. Poodle Put that prop on because it looks so pretty. I do have a good selection of Hydromotives and Machs......Ed