Trim Tab as Wake Plate Install

[smileysteve]

This might be an extremely extraordinary question because I don't have a wedge;

I have a VRide SV23 without a Wedge and enjoy slalom skiing and surfing. I'm considering setting up a "wake plate" "anti-cavitation plate" center trim tab much like the other manufacturer's have, but am trying to figure out some details; Hopes are 1) Better fuel efficiency when cruising 2) More bow cut in rough water, 3) Softer Slalom Wake 4) Less weight required in bow for surfing

I'm mostly looking at Lenco as I don't want the hassle of a hydraulic pump to fill.

1)  Span; 9" or 12"; The Moomba plate is 12x24; so I lean that direction; But, 9" seems it would have advantages in less angular force; quicker and broader range of adjustment. How would the additional 3" of the 12" change the rooster tail, spray, etc? Effectively the 9" seems closer to an interceptor?

2) Chord; 24" or 18"; I think the bottom of the boat is flat enough that both will fit.

Considerations; Moomba is 12x24; Mastercraft/Overtons have a 12x14 option;
 

[Chaabo]

I would be cautious with that experiment! And before you drill holes in your hull...

Ever seen the Scarpa plate that Malibu used to offer?

Basically the same as a center mounted trim tab, absolutely destroys the slalom wake.

I tried once skiing behind our Response with a Scarpa plate mounted. Wake was awful, had a table (good for footin’ I guess) but not good at all for the slalom wake.

[smileysteve]

4 hours ago, Chaabo said:

Ever seen the Scarpa plate that Malibu used to offer?

I have not; though here's a related post; 

I suspect that the dimensions that I'm asking about may have an impact; The wider (chord) a plate, the more the lifting action should be spread out; and the span should change the intensity of the "hook".

I also suspect that, why my experience on the Moomba Outback w/ wake plate was so good was that there was a speed spot not all of the way down, but most of the way down; the idea that it's remotely adjustable based on load should have an impact to its use cases.

The wider chord -- and even longer span (as reduce ability to clear the wave) I do worry, has a potential impact on the surf wave.

 

[Chaabo]

IDK about the Moomba, but the Scarpa Plate is a fairly large “trim tab”.

Here are a couple pictures to give you an idea:

 

[williemon]

I think you will get a more bow down attitude but will only be useful at 20 to. 25 mph to help smooth wake and not have a high bow for ease of driver visibility. May help with footing at faster speeds. No improvement in fuel efficiency since then you will push more bow into water and add drag. I think it will off set surf wake by lifting stern. You need to sink the stern. The moonba if I remember that I read about years ago had a hull that favored a large wake for boarding so a tab like that would ease the wake and lift stern to aid in skiing and lower wakes 

[smileysteve]

3 hours ago, williemon said:

I think it will off set surf wake by lifting stern.

My hope is that by having a tab, I could avoid running lead or a big box in the bow; instead a similar amount of weight could be put midship; this would definitely shorten the wave, but maybe add push.

[williemon]

I think you will find that a tab pushes the bow down by lifting the stern. To surf you should sink the stern. Many I/o owners will use tabs to help holeshot and running attitude but will disconnect them when ready to wake board.i used to do the exact same thing with my I/o back in the day. 

[Cole2001]

Im not sure how much a "wake plate" is really going to help you. Just reviewing its operations, when fully deployed down it creates a smaller wake and allows the boat to get on plane. The higher up out of the water theoretically should make the larger wake. Now with that being said Malibu designed their hulls to not ned this feature, unlike say tige's convex v hull where the boat physically cannot stay on plane without porpoising if the tab is not used. So it's honestly hard to say, I dont think it will help you skiing, surfing it might give you a bit more adjustment. 

[smileysteve]

On 9/18/2019 at 12:42 AM, Cole2001 said:

Now with that being said Malibu designed their hulls to not ned this feature,

Semi correct, yes, Tige has a convex hull; but everybody in this forum posts that you need more weight in the bow, and people are putting 300lbs of lead in on top of 500lbs of water; So, in some ways I'd say that Malibu's hull shape could benefit in many ways from more hook. From the competition standpoint, Nautique and Mastercraft are famous for more hook than Malibu (their flatter but firmer slalom wake) and they've added wake plates to accomplish what I state as my goals. Obviously, the Wedge is incompatible with a center tab, and Malibu has the patent...

Yes, as weight in the bow would, the surf wake would be shorter, but should have more push; the physics also suggest you could add more weight midship and aft, while keeping the bow down.

[02vlxbu]

The older hulls where also never made to have surf tabs on them but they work great.