Alpha 1 hydrofoil question and thoughts...

[Suprathepeg]

When I got my boat it had a stingray hydrofoil on the leg.

I've read all the negative responses and I know that smart tabs are not a good solution but summer is almost done and I'm not going to invest in smart tabs this year. So that said here are my thoughts.

I'm getting a lot of prop slip at speed and I think one of the causes may be that the hydrofoil is in the water at plane, doing so reading it looks like the foil should be above the water once the boat is planing.

So what could go wrong with me shimming up the hydrofoil? The one I have is bolted directly to the leg so I'm thinking longer bolts with 1/2" of nuts as spacers?

 

[ziggy]

So what could go wrong with me shimming up the hydrofoil?

i don't know, maybe break your anti cavitation plate. but that can occur without having the hydrofoil shimmed up off the anti cavitation plate. though maybe more likely since the hydrofoil would not have the full support of the anit cavitation plate.
i had one on my last boat and it did break my anti cavitation plate... it wasn't shimmed up either...
why don't ya take the hydrofoil off and see how it works w/o any mods.... i did that and found the boat i had worked fine for me w/o the hydrofoil.

 

[southkogs]

I'm kinda' thinkin' the same thing as Zig. I'm not a big fan of foils, though a lot of folks do like them. My boat had one when I first got it. I took it off and noticed no change in the performance of the boat whatsoever.

 

[NYBo]

Third vote for removing it and seeing how the boat does.

 

[thumpar]

They usually don't work well with I/Os. Just take it off. If they were that great the factory would put them on or offer it as an option.

 

[smokeonthewater]

Toss it in the dumpster..... I've probably thrown away close to a dozen of them.

 

[Watermann]

I sent one of those things to a guy in the mail that came off my LU, he thought it would help and I didn't argue. I was just happy it was out of my garage and not on my boat..

 

[Bondo]

So what could go wrong with me shimming up the hydrofoil? The one I have is bolted directly to the leg so I'm thinking longer bolts with 1/2" of nuts as spacers?

Ayuh,.... Sounds like a sure fire way to bust the cav-plate off the drive,....

 

[rallyart]

I would not shim it up off the cavitation plate. Taking it off is easy and you will probably find it makes no difference in the prop slip you have. On my Stingray I got a dramatic decrease in cavitation on hard corners after the foil was installed. In essence it is just a bigger cavitation plate with some other benefits. I suspect your prop slip is more likely caused by damage to the prop than the foil, but it is only four screws and nuts to remove it so that is a smart choice. You may have to adjust your steering trim tab after it comes off.
Every boat is different so go through steps, one a t a time, to see what makes a difference.

 

[Suprathepeg]

The prop is new and mint. The foil is fully submerged when on plane. I think the foil is causing a lot of drag.

 

[rallyart]

It creates some, Mine dropped the top speed on my 1980 18' from 43 to 42 with 170 hp. Remember that the hull is further out of the water with the foil on.
But, as I said, take it off and see what it does. That is an easy test. I just would not space it up.