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avk
05-09-2000, 10:51 PM
I am about to install some Bennett tabs on my Classic 18. I have seen some installed close to the chine as per Bennett and also some placed nearer the outdrive. Anybody has any thoughts about placement?

RickR,GroveCity
05-10-2000, 06:45 AM
avk
What are the specs of your Donzi?
Which tabs did you get?
What is your intended use of the tabs?

If you got the regular Bennetts I agree with madpoodle but;
If you purchased the Bennett Sport tabs, AND you have a High Performance 18 (above 65MPH) you want to mount them as closer to the keel without interfering with the drive (when turned).
At speed so much of the hull is out of the water your tabs will not be effective if mounted too far out.
Also I would reccomend mounting the bottom surface of the tabs 1/8" above the hull.
BTW My Bennett Sport tabs are mounted 6" inside the chine, too far out for my 18.
If you want a pic, email your address to me.

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RickR mailto:riggerb@aol.comriggerb@aol.com</A>

[This message has been edited by RickR,GroveCity (edited 05-10-2000).]

RickR,GroveCity
05-12-2000, 08:29 AM
Alan
I am using the 12X9 Sport Tabs also.
If your primary use will be for slow speeds in the "Chop" farther apart is better.


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RickR mailto:riggerb@aol.comriggerb@aol.com</A>

Forrest
05-12-2000, 12:42 PM
Sometimes you don't want 'em to be that effective at high speed. A little down tab will go a long way if they are mounted close to the drive. In other words, the tab controls may be very touchy at high speeds. And ScottB is right, they will take a heavy beating mounted close in, too. I recommend that they be mounted close to the chine.

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Forrest

[This message has been edited by Forrest (edited 05-12-2000).]

kingair
05-13-2000, 07:34 PM
Hey, just a piece of FYI. At the factory we mounted the tabs 1/2" above and parallel to the bottom and aligned with the point where the v-portion of the bottom turns horizontal (@ 2 - 2 1/2" from the side of the boat.) A 't' square aids in finding the intersect point and help to draw a line that is parallel with the bottom. We would also mount them with an addition 3/4" of up angle from parallel to the long axis of the bottom. You will find that 12" tabs are more than effective there.
at low and high speeds.

Later gators!
Philip

p.s. if you

Hotboat
05-14-2000, 08:59 AM
Just purchased a set of Trim Master tabs. They recommend placement to be 1/2" above the bottom of the boat and 3/4" up at the trailing end. (Same as Kingair recommended) These are 12x12 sport tabs. Trim Master will sell direct to the comsumer via the internet with a very good discount.

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Hotboat

RickR,GroveCity
05-14-2000, 05:51 PM
FYI on high performance applications of tabs
On my BBC 18 I use the port tab to counteract the torsion of the right hand prop.
My 12X9 Sport Tabs are mounted 6" inside the chine flush with the hull bottom.
As speed increases I have to use more port tab as the hull rises out of the water and rides on the inside strakes. Up to the point where I am 3/4 down on port tab http://206.150.187.82/ubb/eek.gif. 3/4 down is too much angle at high speed.
If you'll look where the inside strakes are you can see where to mount the tabs in relation to the wet part of the hull.

BTW Some Rocket Scientist mounted the 12X9 Trimmasters on my 22, 1 1/8" above the hull bottom 6" inside the chine. They are usless above 55 MPH. I plan on removing the Trimmasters and installing 12X12 Sport Tabs a little closer in, 1/8 above the bottom.

Kingair and Hotboat
Why would you mount the tabs 1/2" above the bottom on a 18 Donzi? (An 18' deep v with 260+hp)

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RickR mailto:riggerb@aol.comriggerb@aol.com</A>