Trim Tab Size

FreeBeeTony

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May 15, 2002
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A friend of mine gave me a trim tab set-up w/o the tabs themselves. I have a '78 20' Grady White W/A, what size tabs does this size of a boat require?
 

Knightgang

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Oct 6, 2003
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Re: Trim Tab Size

According to some of the cahart shtat I have looked at regarding trim tabs, you would need tabs sazed at about 12"x9" for that application. This size should be good for most boats up to 22' LOA.<br /><br />Good luck
 

Tabman

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Feb 21, 2002
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Re: Trim Tab Size

Tony,<br /><br />Trim Tabs that are 18" x 9" or 12" x 12" would be the best choice for your Grady. Let me know if you have any questions we can help you with.<br /><br />Tom McGow<br />Bennett Marine
 

Boatist

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Apr 22, 2002
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Re: Trim Tab Size

Tony<br />I cant't disagree with Tabman as he knows his stuff, but I love my tabs on my 21 foot boat and they are 24" wide by 12" deep. This is on a Creatliner Aluminum. I will admit I never really put them all the way down except when useing them to keep the boat straight when anchored on light current days. Sort like a stern sea anchor.
 

Bondo

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Apr 17, 2002
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Re: Trim Tab Size

Yep,<br />No Doubt, Tabman Is the Authority.....<br />But, I bought the 12"X18" for my little 21' starcraft..... I use them for Trolling Brakes.....<br />I Can't see any down-side to having tabs that are Too Big.......<br />That little bit of tin makes my boat Feel/Handle like it was 5' Longer............. :D
 

Tabman

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Feb 21, 2002
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Re: Trim Tab Size

Bigger is better, and there is no real downside to having them too big. 18 x 12 would be OK if you want on the 20, but 24 x 12 would be a bit large.<br /><br />I have a 20 Aquasport Walkarounf with M120 10" x 12" Sport Tabs. There are equal to a 12" x 12" standard Tab, and they are perfect for my boat and my use.<br /><br />Tom<br />Bennett Marine
 

FreeBeeTony

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May 15, 2002
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Re: Trim Tab Size

Bondo, why would the tabs make the boat feel/handle like it was 5' longer? Is this a good thing?
 

Bondo

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Re: Trim Tab Size

Hi Tony,<br />Well, Think About It..........<br />Any time you Extend the Planing Surface, You are, in effect, creating a Longer Boat......<br />Just the opposite of the Newer Euro-Style boats you see where a big platform is cast into the boat.... You're Paying for a boat 2'Longer than it Really Is..... It's the Planing Surface that Carries the boat........<br />Go for a ride in an 18' boat... It'll Beat you to death, Compared to Your 20'er, in the Same Seas..... Then go for a ride in a 23'er.... You'll be ready to Trade Up :D ........ And a 25'er will ride that much Better, Again.....<br />Commonly Know as 2ft.Itiss......... ;) <br />
Is this a good thing?
It Sure Is In My Book........................... ;)
 

cobra 3.0

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Jul 31, 2003
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Re: Trim Tab Size

Can we conclude that an increased planing surface increases the speed of the boat?
 

Bondo

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Re: Trim Tab Size

Possibly, But Not Always........<br />By Increasing the Planing Surface, You're Increasing Drag also......<br />But, If by Increasing the Rear-most Planing Surface, you can Decrease the Forward-most Planing Surfaces, there for Decreasing the Total Drag of the Hull,<br />Yes, you Should Go Faster.................... :D
 

Boatist

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Apr 22, 2002
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Re: Trim Tab Size

I would conclude that trim tabs actually slow your top speed some. Top speed if the boat is set up right should be with the bow as high as safe and as little wetted surface as possible. If your boat was set up so you have to trim your motor off vertical to adjust the boat ride then the tabs could make it a little faster as you can keep your drive vertical and adjust the boat trim with the tabs. On my boat I saw no difference at all. Hydrolic trim tabs is the best thing I have ever added to my boat. Off shore with 6 to 8 foot swells you are not going to run 20 MPH to get on plane. Slow down and you plow the whole day. With the tabs you slow down to a safe speed then use the tabs to adjust your boat trim to lower the bow and cut the waves for the best ride and most fuel MPG. In short you can adjust your boat at any speed for a good safe ride. I will never own a boat without helm adjustalbe trim tabs. Adjustable trim tabs worth every penny.
 
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