Hydrofoils?? Do they do what they claim??

[carmjon1]

We have a '82 trihull with a 70 HP Merc. I've seen hydrofoils in various catalogs and wondered if they actually improve gas mileage and decrease plaining speed. I'm normally not a believer of adding aftermarket stuff to my cars or boats, but I am very curious about these hydrofoils. Do they do what their manufacturers claim? If so, what's the best one to go with - Sting Ray, SE Sport?
Could use some advice from those who have tried these.
Thanks!!

 

[studlymandingo]

Re: Hydrofoils?? Do they do what they claim??

If you do a search here on the hydrofoil, you will find hands down that the smart tabs are much better for what you are looking for. And yes, such a device will most likely significantly enhance the performance of your boat.

I had an old Glastron with a 70 'rude on it; with 4 people on board, everyone had to go as far forward as they could possibly get. Put on the Smart Tabs and it would jump right over the wave without a problem; it was like a different boat.​

 

[Bigjohn1]

Re: Hydrofoils?? Do they do what they claim??

There are different schools of thought on these devices. Some say that if they were so good, why don't the outboard manufacturers either install one at the factory or mold their skegs differently. From the manufacturer's standpoint, I think there is no way they can tell what hull a given engine will end up hence they design their outboards the way they do.

Now with all that said, I am a believer in them for certain applications. Personally, I use one (doelfin) to help my center console plane at a lower speed when trolling on the ocean. Before I installed it, the hull would not plane at the speed I trolled at (8-10 knots) and now it does. As for speed and/or fuel economy improvements, I cannot speak to that since I have done no real comparison measuring.

 

[WillyBWright]

Re: Hydrofoils?? Do they do what they claim??

If they claim that they mess with handling, increase drag, break antiventilation plates, and slow you down, then yes they do what they claim.

 

[steelespike]

Re: Hydrofoils?? Do they do what they claim??

As I've said a 100 times I've had very good luck with the Doelfin in 2 different boats,a 15 ft Starcraft w 50 hp rude and an 18 ft Cobia w 120 i/o.Much easier to plane,better handling,less bow rise.Much easier for two 5 footers to see over the bow when coming out of the hole,stays on plane at lower speed.
That being said I now consider the hydrofoil a last resort.The only way to go is something like the smart tabs.Placement on a tri hull may be difficult but
results may be worth getting them fitted.

 

[tashasdaddy]

Re: Hydrofoils?? Do they do what they claim??

my opinion is i have 2 sets in the shed i've taken off motors i've bought.

 

[tmcalavy]

Re: Hydrofoils?? Do they do what they claim??

If your boat has trouble planing a whale-tail might help but it will cost you a little speed and fuel efficiency. Check to see that your outboard is mounted correctly...anticavitation plate should be within 1 inch of the bottom of the hull, up or down, when the outboard is straight up and down. I had one on a 15 foot 73 Ebbtide trihull with a Merc 500 50 hp and it helped the old girl plane faster, but it was slower in the turns also. If you try all the different trim settings and still have trouble getting on plane, you might want to check under the floor of your trihull...might have saturated flotation foam under there, making it heavier than from the factory. If the floor is solid, indicating that foam is sound, try moving some stuff forward...like your favorite fishing Bubba or the MIL.

 

[thurps]

Re: Hydrofoils?? Do they do what they claim??

Made a new boat out of my 13 whaler with a 40hp Johnson. A ride at plane on an ocean chop is almost bearable now.

 

[Outrage22Cuddy]

Re: Hydrofoils?? Do they do what they claim??

I'm just having too much fun posting my 1st day on this site.

When my boat had twin engines, I added 2 Stingray stabilizers. They did reduce my planing speed, chine-walking & improved the ride quality. They also slightly reduced my mpg(yes, I have a Flowscan) & top speed. So, I'd say it's a give/take that changes the characteristics of your boat. Now that I'm down to 1 engine & drive at slower speeds, I think the device helps more than it hurts. For a high-speed twin engine boat, I'd say get trim tabs or leave it alone. Just my 2 cents.

 

[QC]

Re: Hydrofoils?? Do they do what they claim??

Trim tabs, helm adjustable or Smart Tabs, are a much better alternative and do NOT have ANY of the negative characteristics . . . Aftermarket stuff is very appropriate in the marine industry as applications differ so much and the multitude of manufacturers compared to auto. It also opens the door for cheap carp that may work sometimes, but is on balance bad news . . .

 

[tommays]

Re: Hydrofoils?? Do they do what they claim??

To me the Fin is something that time has passed buy

When you only pick was full bennet trim tabs it was a good idea

Now with the price of smart tabs its not worth putting up with the down side of the foil


Tommays