wings on your outboards????

[will941s]

Re: wings on your outboards????

If there were one manufacturer of outboards, at one hp.....and one style/make of boat all set up the same exact way without T&T you could say without a doubt "that product works, or does not work". But, with sooooo many variations of rigs and motors it's impossible. The foils may work wonders with some boats and work like crap with others. The only way to correct a problem is with trial and error. No doubt some of the same theories that work in avionics work in marine applications, due to lift and tilt by flow. Which is why some planes need large wings, and some need small wings. Some boats may need a little more cavitation plate, and some don't. Outboards are designed to run on a specific platform for that model, hp, and transom height. Then joe blow throws it something else and is unhappy with the performance, puts on some foils and the angels sing...runs like a champ. Someone else tries it on another rig and it runs worse because the motor needs less motor or lift. One thing though....Mercury says "use of Hydrofoils on some smaller v-bottom boats may cause the motor to dig in a turn, therefore ejecting the passangers".

 

[ClassyGlassy]

Re: wings on your outboards????

I like a controversial thread

I have a Stingray installed on my '73 Evinrude 65hp and it planes my '72 Invader Trihull much quicker, runs at a higher speed, and turns easier at the higher speeds.

But opinions are like other things everyone has......they all stink worse when it's not yours......

http://www.marine-dynamics.com/index.html

 

[ondarvr]

Re: wings on your outboards????

If there were one manufacturer of outboards, at one hp.....and one style/make of boat all set up the same exact way without T&T you could say without a doubt "that product works, or does not work". But, with sooooo many variations of rigs and motors it's impossible. The foils may work wonders with some boats and work like crap with others. The only way to correct a problem is with trial and error. No doubt some of the same theories that work in avionics work in marine applications, due to lift and tilt by flow. Which is why some planes need large wings, and some need small wings. Some boats may need a little more cavitation plate, and some don't. Outboards are designed to run on a specific platform for that model, hp, and transom height. Then joe blow throws it something else and is unhappy with the performance, puts on some foils and the angels sing...runs like a champ. Someone else tries it on another rig and it runs worse because the motor needs less motor or lift. One thing though....Mercury says "use of Hydrofoils on some smaller v-bottom boats may cause the motor to dig in a turn, therefore ejecting the passangers".

You're so very correct, the only part that people must understand is sort of about what you mentioned on avionics and what Merc says about turning. If these things come into play (hydrodynamics, bad handling) its because the setup is most likely wrong, when used correctly the foil is not in the water affecting handling, nor will any wing (foil) effect take place. And again only a few boat and motor combinations will benefit from using one.

 

[ClassyGlassy]

Re: wings on your outboards????

I don't agree that only a "few" will benefit from a hydrofoil!

read this: http://www.marine-dynamics.com/how.html

 

[ondarvr]

Re: wings on your outboards????

I don't agree that only a "few" will benefit from a hydrofoil!

read this: http://www.marine-dynamics.com/how.html

If you read the related thread I linked you'll see what they can do to help.

Most of what is listed as a benefit in the advertising for this type of product would be better accomplished by tabs. Plus most of what the owners want to fix is better done with tabs, but almost every situation is different and needs to evaluated independently.

 

[ClassyGlassy]

Re: wings on your outboards????

I'll agree with that!

 

[pecheux]

Re: wings on your outboards????

They are also weeds collectors if you use your boat on lakes with lots of vegetation. Had them on my 115 hp on a fishing boat ... took em off for that reason.

 

[JimS123]

Re: wings on your outboards????

The marketplace controls what's available for sale.

If hydrofoils didn't work for some applications, the original product would have gone out of business long ago, rather than other companies coming into the market as competitors.

If there were inherent dangers with the product, the lawyers would have driven them off the market long ago.

If all the problems with broken cavitation plates, bearings, weed pickup, etc. were widespread problems, word would have gotten around and potential new customers would have shyed away.

Mercury won't design their cavitation plate larger because then it would not be optimum on certain rigs. You can't explain that to some people. Thus, they can't endorse it because it makes them look like their design is inferior.

I had a performance issue 25 years ago and a Doel Fin improved my performace in all respects. Its still on there! Many years ago Trailer Boats Magazine did a shootout comparing all of the brands available at the time on 2 boats - an outboard and an I/O. Data like time to plane, top speed and fuel economy were compared with and without the foil. That data was good enough for me.

Makes no matter to me whether anybody else uses them or not. To say they may or may not work depending upon the circumstances is a reasonable statement. But to downright knock them with no first hand knowledge is NOT right.

 

[achris]

Re: wings on your outboards????

... But to downright knock them with no first hand knowledge is NOT right.

I have first hand knowledge. As an ex-dealership owner I tested boats for a living, with and without 'hydrofoils'. The one thing that stood out above anything else, and without exception, was the tendency to cause a boat to 'bow steer'. That, and that alone, makes them dangerous, especially in the hands of the inexperienced.

Chris....

 

[ondarvr]

Re: wings on your outboards????

I have first hand knowledge. As an ex-dealership owner I tested boats for a living, with and without 'hydrofoils'. The one thing that stood out above anything else, and without exception, was the tendency to cause a boat to 'bow steer'. That, and that alone, makes them dangerous, especially in the hands of the inexperienced.

Chris....

You didn't say what type of boats these were, but bow steer and other negative results tend to be on I/Os or when the OB wasn't set up correctly to use a foil. That is, if the set up even needed, or could benefit from one in the first place.

 

[ClassyGlassy]

Re: wings on your outboards????

If I poor RedBull into my outboard will it get it's "wings" ?

 

[achris]

Re: wings on your outboards????

You didn't say what type of boats these were, but bow steer and other negative results tend to be on I/Os or when the OB wasn't set up correctly to use a foil. That is, if the set up even needed, or could benefit from one in the first place.

Many different set ups... Outboards, I/Os, runabouts, cabin cruisers, fibreglass, aluminium.... Most of them were customers boats who had performance problems, and unless the boat was badly underpowered I would recommend the 'wing' be removed.

I've also seen quite a few broken AV plates because of them. Not to mention plenty of cut knees! They are also a PITA when trying to remove a leg (I/O or OB) for servicing!

If a boat needs stern lift (which is what 'wings' are supposed to do) then the boat will perform far better with tabs, not wings.

Chris....

 

[ondarvr]

Re: wings on your outboards????

If a boat needs stern lift (which is what 'wings' are supposed to do) then the boat will perform far better with tabs, not wings.


This is the problem, they don't do this that well, although some of the marketing will indicate they will. Rarely are they used for what they actually can do and what they can do isn't needed all that often. Tabs do work much better for stern lift, I would never recommend a foil for this problem. Tabs and foils do totally different things, but the positive effects can overlap some.

 

[JimS123]

Re: wings on your outboards????

without exception, ....the tendency to cause a boat to 'bow steer'. That, and that alone, makes them dangerous, especially in the hands of the inexperienced.

Chris....

That's a mighty finite statement. I try to avoid the words "never" and "always" because then you will always be be proven wrong...LOL (oops)

Anyway, all kidding aside, yes, bow steering is very dangerous. If that were the case with my boat, I would rip it off right away.

PITA to get the leg off?...that's your problem, you're the mechanic and I'm paying you to do the work. All I care about it whether it works.

Cut legs?...maybe. Never done it myself, but have on the SS prop, which is sharper.

Bow steer? I would invite you to take a ride in one or all of my three boats. Fiberglas, aluminum, Cuddy, Bowrider, OB and I/O. Two have max HP and the third is certainly not underpowered. No bow steer on any of them.

 

[JimS123]

Re: wings on your outboards????

If a boat needs stern lift (which is what 'wings' are supposed to do) then the boat will perform far better with tabs, not wings.


This is the problem, they don't do this that well, although some of the marketing will indicate they will. Rarely are they used for what they actually can do and what they can do isn't needed all that often. Tabs do work much better for stern lift, I would never recommend a foil for this problem. Tabs and foils do totally different things, but the positive effects can overlap some.

Sounds like you have a lot of experience in this regard. For everyone's benefit, can you itemize the different things that tabs and foils can do? When would a foil be recommended, and when would a tab be recommended?

 

[ondarvr]

Re: wings on your outboards????

Sounds like you have a lot of experience in this regard. For everyone's benefit, can you itemize the different things that tabs and foils can do? When would a foil be recommended, and when would a tab be recommended?

The link in my first post in this thread covers most of what a foil can do well.

 

[achris]

Re: wings on your outboards????

Ondarvr,

You were asked in the other thread to explain exactly what a fin/wing/hydrofoil is designed to do, and how they should be set up.... You were asked again in this thread... You are yet to answer that question in either thread.... In fact, in the other thread you challenged someone, anyone, to tell YOU what they are designed for... That smacks very much of someone who is talking out of the top of their head (or any other part of their anatomy).

I am beginning to think of you as a typical politician... Talks a lot, but says nothing....

Now, put up or shut up. What are they designed to do and how should they be setup, (as you keep saying that nobody sets them up right)?

Chris........

 

[ondarvr]

Re: wings on your outboards????

I did explain what they do in the previous thread, the reason for the link and not another explanation is because its been discussed so many times it can get tiring to retype it all. The reason for the challenge in that thread is because people always give an opinion that is normally based on miss-use of the product and then people claim they can never be of any benefit and are junk. If someone is going to claim they don't work, they at least need to know what it can do and how to set it up.

The truth is they rarely get used for what they can actually do and the claims made for them on the label while "somewhat" accurate, don't say how to set it up, or how it works. If you use it incorrectly you will see the negative affects you and others frequently experience. If one can be useful at all, and that is ?if?, plus if you set it up correctly, you won't see these issues.

The foil allows you to do one thing and that's raise the motor, that isn't really possible on an I/O, so you're stuck with some possible (likely) negative affects. A foil allows you to raise the motor by not letting the prop ventilate and suck air as easily as it would without one, so you can raise the motor higher. With the motor higher it has less leverage on the hull so there is less bow rise, this may help porposing too. Plus as you raise the motor there is less of the gearcase in the water, this equals less drag and a higher top speed with a few extra RPMs. This helps with mileage too. So in a way the label is correct.

At low speed a prop that's too near the surface will suck air under hard acceleration, but at speed the prop can be right at the surface and still get a very good bite. The foil just blocks the surface above the prop so air can't be sucked down when the motor is mounted higher.

The real benefits have nothing to do with it dragging in the water, especially at speed, this is where the all the handling issues come from, also the lower top speed and worse mileage.

If you just bolt one on and head for the water you will most likely see little if any improvement, the bow may stay down better and you may stay on plan at a lower speed, but unless you got lucky, it will be dragging in the water, slowing you down and possibly creating other problems. This is how most people use them, so you can see why people dislike them.

I would say that most boat and motor combinations won?t really see any improvement with a foil, but some can benefit a great deal by using one.

By just reading the label on most of these products the hype says it will help with just about every issue you could ever have while boating, which is very misleading because it doesn?t actually say how to get any of the possible benefits.

Tabs do a totally different job, are much more useful and have almost no negative affects even if you don?t need them.

In another thread about these devises I said comparing tabs to foils was like comparing a hammer to a crescent wrench. A hammer is designed to beat on things and they do it well, you can also beat on things with a crescent wrench, and it sort of works, but if you use a crescent wrench to pound in nails, don?t start complaining about how it doesn?t do a good job at it.

A hydraulic jack plate would be a much better way to adjust motor height and with the correct prop it would yield far better results, buts its a costly way to do it.

 

[achris]

Re: wings on your outboards????

Well, I guess I've been put in my place... Thank you for the info. I have never seen anything like this on the packaging of a fin or the literature from the fin manufacturers. This does explain a lot and I bow to your superior knowledge on the subject.

Just one question... Why do the manufacturers put all the BS on the packaging?

Chris........

 

[ondarvr]

Re: wings on your outboards????

I think if they said you needed to adjust motor height there would be far fewer people buying them, as most wouldn't know how to do it, this would also turn off the I/O owner. Plus even when used wrong they tend to let the boat plane faster, which is easily noticed by the owner, he may not notice a drop of 1 or 2 MPH though.