Hydrofoil

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chriscraft254

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Re: Hydrofoil

Please go into it, in detail if possible.

You still don't seem to get it, there is no lift from the foil when used correctly, there is no lift from the center/middle. If you have an I/O forget it, it will most likely be a waste of money.

I already explained it. The only time it isn't in the water is when it is on perfectly flat calm water where the boat isn't going through waves. Look at your anti-cavitation plate the next time you go across a wake, you will see, it dips down into the water. Then amagine that foil doing the same thing on a larger scale.

The foil is great when it is out of the water, but how often is that, even when as you say, properly set up?
 

ondarvr

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Re: Hydrofoil

So... have you used Smart tabs?

Yes, I know exactly how they work, fully adjustble tabs too. They are of far more value than a foil for just about every problem a boat owner wants to fix.

In fact a foil doesn't fix anything, it only allows you to do other things that may help performance.

And unlike where tabs may help with under powered hulls, foils can help more with HP at the upper limits or over powered hulls.
 

chriscraft254

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Re: Hydrofoil

Yes, I know exactly how they work, fully adjustble tabs too. They are of far more value than a foil for just about every problem a boat owner wants to fix.

In fact a foil doesn't fix anything, it only allows you to do other things that may help performance.

And unlike where tabs may help with under powered hulls, foils can help more with HP at the upper limits or over powered hulls. QUOTE]

Ok, I'm listening, please do explain the above.:)
 

ondarvr

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Re: Hydrofoil

I already explained it. The only time it isn't in the water is when it is on perfectly flat calm water where the boat isn't going through waves. Look at your anti-cavitation plate the next time you go across a wake, you will see, it dips down into the water. Then amagine that foil doing the same thing on a larger scale.

The foil is great when it is out of the water, but how often is that, even when as you say, properly set up?

I took a great deal of time dialing in my setup, the foil never drags in the water, my AV plate is well above the surface, this is what the foil allows you to do. If it does drag in the water even after you've done the setup work and it create probelms...then it's like I have said many times before, it is of no value and won't work CORRECTLY on that hull, motor, prop combination.
 

chriscraft254

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Re: Hydrofoil

I took a great deal of time dialing in my setup, the foil never drags in the water, my AV plate is well above the surface, this is what the foil allows you to do. If it does drag in the water even after you done the setup work and it create probelms...then it's like I have said many times before, it is of no value and won't work CORRECTLY on that hull, motor, prop combination.

Cool, how many rpms did you gain in top end and what was the rpm range for the motor you had? And would you say it would have been much easier and more benificial to just install tabs to begin with instead of having to do all that?
 

ondarvr

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Re: Hydrofoil

Yes, I know exactly how they work, fully adjustble tabs too. They are of far more value than a foil for just about every problem a boat owner wants to fix.

In fact a foil doesn't fix anything, it only allows you to do other things that may help performance.

And unlike where tabs may help with under powered hulls, foils can help more with HP at the upper limits or over powered hulls.QUOTE]

Ok, I'm listening, please do explain the above.:)

With a low HP setup there is less chance of ventilation because the motor doesn't have the HP to spin the prop and suck air as easily.

There are much better ways than using a foil to get the same job done though, and tabs can be part of it. The far better than a foil method is a hydraulic jack plate, and an assortment of SS props. This allows you to have the prop deep enough in the water for a good bite under hard acceleration and then raise it to the exact right height for your speed and load, plus water conditions, should I say tabs are terrible because they can?t do this, or should I just say they are a different tool with a different purpose.

A foil acts as sort of a poor man?s hydraulic jackplate, not a motor mounted trim tab.
 

chriscraft254

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Re: Hydrofoil

With a low HP setup there is less chance of ventilation because the motor doesn't have the HP to spin the prop and suck air as easily.

There are much better ways than using a foil to get the same job though, and tabs can be part of it. The far better than a foil method is a hydraulic jack plate, and an assortment of SS props. This allows you to have the prop deep enough in the water for a good bite under hard acceleration and then raise it to exact right height for your speed and load, plus water conditions, should I say tabs are terrible because they can?t do this, or should I say they are different tool with a different purpose.

A foil acts as sort of a poor man?s hydraulic jackplate, not a motor mounted trim tab.

That I would agree with. The jackplate has far more controll than any foil. Even with a jackplate , I would be running tabs. But alot don't,especially on bass boats.

I think you may take what I say as putting down the foil. I don't try to do that, I just say there are much better options available. And in my mind, that makes them a waste of money. I'm hittin the sack, have a good morning.
 

ondarvr

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Re: Hydrofoil

Cool, how many rpms did you gain in top end and what was the rpm range for the motor you had? And would you say it would have been much easier and more benificial to just install tabs to begin with instead of having to do all that?

Again tabs and foils do two totally different things, tabs would have done nothing to help my performance or ride.
I needed to reach 5,500 RPM (top end of RPM range) and If I remember correctly I was at about 4,100 or so. The first step in increasing your RPMs is not going to a different prop, it?s to optimize your current setup, so that?s what I did. I fiddled around with trim and motor height, but ventilation was a big problem, if the motor was mounted low it wouldn?t ventilate, but I lost RPMs, as I raised it the RPMs and top speed improved, but I had to baby the throttle to get there.

I had a foil sitting on the work bench and decided to try it. What I was able to do was raise the motor one hole higher than ever before, which increased the RPMs to just over 5,400 and dramatically reduce the ventilation, it was reduced to the point where I could nail the throttle from a dead stop and have almost no ventilation. Prior to installing it I could spin the prop easily up to about half throttle.

Tabs would have been of no value because there was little bow rise and no porpoising to fix.
Should I say tabs are horrible because they wouldn?t help in this situation, or should I just say they weren?t the correct tool for the job.
 

ondarvr

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Re: Hydrofoil

I think you may take what I say as putting down the foil. I don't try to do that, I just say there are much better options available. And in my mind, that makes them a waste of money. I'm hittin the sack, have a good morning.

This is the problem, you still seem to think they are supposed to do the same thing.
 

ondarvr

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Re: Hydrofoil

I have used this comparison before. A guy has a hammer and a crescent wrench, both can be used as a hammer and frequently are. When the crescent wrench is used as a hammer should the guy complain that it doesn?t do a very job as a hammer?

This is what you're doing when comparing foils and tabs.
 

ondarvr

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Re: Hydrofoil

The jackplate has far more controll than any foil. Even with a jackplate , I would be running tabs.

Jackplates also cost slightly more than a foil, that's why I said it was a poor man's jackplate.

There is no problem running a jackplate and tabs on the same hull, you could run tabs and a foil too, there's no probelm with that combo, but I can't say a jackplate and foil would be needed at the same time.
 

TMALEGA

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Re: Hydrofoil

Not to cause a even bigger arguement but on the set of tabs i got last night it said in very bold letters and even on the install dvd not to run boat the fin and tabs. It would cause either very bad issues or cancel each other out and not allow either to do what they are suppose to do. When i looked at the fin before i got the tabs it said not to use them together also. Except it said if that is what you are having to do that there is a large underlying problem and to have the boat checked out.
 

ondarvr

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Re: Hydrofoil

Not to cause a even bigger arguement but on the set of tabs i got last night it said in very bold letters and even on the install dvd not to run boat the fin and tabs. It would cause either very bad issues or cancel each other out and not allow either to do what they are suppose to do. When i looked at the fin before i got the tabs it said not to use them together also. Except it said if that is what you are having to do that there is a large underlying problem and to have the boat checked out.

Not knowing what boat you have I can say this.

They are expecting you to do what 99.9% of the people do with foils, they bolt em on and head to the water with no thought of even making any adjustments in motor height. Or they figure a very high percentage of buyers will have I/Os where no adjustments can be done. In these two cases they are 100% correct, you wouldn't want the two products on the same boat. Heck, if you don't make any adjustments just adding the foil alone can cause some scary issues.

A foil "may" allow you to raise the motor, tabs don?t have any affect on that aspect of performance.
 

JimS123

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Re: Hydrofoil

I in no way defend how they are marketed or advertised, and for the most part they don't work correctly on an I/O. What's strange they rarely ever say how to set one up correctly.

We have foils on two I/Os. Both are stern heavy. One is a 22' with a very long Cuddy at the bow and a relatively small cockpit with aft seating right at the transom. The other is a 19' bowrider with a 9.9 kicker and extra gas tanks located under the aft jump seats.

In both cases, the performance out of the hole has been fantastic! ZERO bow rise, tubing is better and the top end was increased by 2-3 mph because it allowed higher trim and higher engine rpm.

Just bolted em on and went. ZERO negatives. We couldn't be happier.

Makes no matter to me whether anybody else likes em or hates em. If I wasn't 100% satisfied i'd take em off.

One caveat - all 4 foils I bought over the years were DoelFins @ about $39 each. To me the design and shape intuitively is superior to the others that stick way out the back.
 

chriscraft254

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Re: Hydrofoil

Not to cause a even bigger arguement but on the set of tabs i got last night it said in very bold letters and even on the install dvd not to run boat the fin and tabs. It would cause either very bad issues or cancel each other out and not allow either to do what they are suppose to do. When i looked at the fin before i got the tabs it said not to use them together also. Except it said if that is what you are having to do that there is a large underlying problem and to have the boat checked out.

The first job of the Nauticus tabs that I am assuming you bought, is to provide lift while getting on a plane with your boat. With a foil attached at the same time, the boat could either end up with way to much lift or added stress on the foil/outdrive due to the added pressure of the boat being pushed up faster with the tabs. Basically the foil or the tabs can counter act the performance of the other.

There is no reason to run a foil if you install tabs.
 

ondarvr

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Re: Hydrofoil

There is no reason to run a foil if you install tabs.

This is the problem, even after explaining it, people don't seem understand the difference in the two products and how they each work.

I'm not saying that every boat will benefit by having both products, I'm not even saying every boat will benefit from just a foil, only that because of the different things each does they may work very well together on the same hull.

You keep saying stuff that show's you don't grasp what a foil may do, you notice I didn't say will, only may. Until there is better understanding of the subject it's difficult to discuss the possible benefits.
 

ezmobee

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Re: Hydrofoil

This has gotten completely friggin' circular. Closed.
 
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