Hydrofoil vs. Permatrim?

D

Doryman

New member
The 22 I am picking up next month is equipped with non-Permatrim hydrofoils on the twin 40s. They look something like THIS, but I don't know if this is exactly what is installed on the motors now. Specifically, I am not sure if the edges are turned down. My question is, what is the wisdom of the collective about this type of hydrofoil compared to actual Permatrims? Would there be any significant advantage in switching over?

Thanks,
Warren[/url]
 
Warren-

I think the overall conclusions about the advantages of the Permatrim over most other hydrofoils come own to the effects of the longer foil body and the down turned edges.

The longer body makes for a longer lever arm, which effectively (sort of) lengthens the waterline and reduces pitching more than the wing like foils.

The down turned edges also make for better steering, and also work better to prevent cavitation (really ventilation) during turns.

That's most of it, as I remember, anyway!

Joe. :teeth :thup
 
Warren, I would give those things a try. If you're not satisfied with the way they make the boat behave, then consider going to Permatrim units. My suspicion is that they are made from a plastic, and perhaps prone to breaking, but it won't hurt at all to see how they work....

Congrats on the new boat.

Steve
 
I used these on twin 250HP alpha one sterndrives on a 30-ft Sea Ray Cruiser with no problems. It was when they originally came out and I was not aware of the Permatrims.

If you decide to replace your units you may have a problem with bolt hole pattern with the permatrims. You may have to have the existing holes filled and ground down by a welder before installing a new hydrofoil.
 
warren I think Terry from last dance has them on his boat same 40hp motors he says they work fine I would try them like others have said and then if need be then go to permatrims

Are you going to use the cd-22 for traveling and the 255 for staying up in Washington? Travel safe
 
jennykatz":1lb34au9 said:
warren I think Terry from last dance has them on his boat same 40hp motors he says they work fine I would try them like others have said and then if need be then go to permatrims

Are you going to use the cd-22 for traveling and the 255 for staying up in Washington? Travel safe
Click to expand...

Jim, yeah, that makes the most sense, to try out what is on there first, but I was curious what people would have to say about how they compare to Permatrims. There are several discussions on the board about choosing between Permatrims and trim tabs but not between hydrofoil designs.

We originally were looking for a 19 to use for fishing, something easier for me to use singlehanded (launch/retrieve, etc.) and future trailering behind an RV. When Jeff's 22 came on the market the price and how it was rigged was so attractive we decided to go with it instead of a 19. Plus, the 22 holds its value best of all the C-Dory models. With this boat I will be much more likely to trailer solo down to Everett or Cathlamet, etc.

Warren
 
I had the Honda-branded foil on my motor and it seemed to lift the rear of the boat excessively. The Permatrim performs better on my 16 Cruiser.

-- Chuck
 
Many of the cheaper foils are plastic--as noted tend to break, will age and chip, and they are not stiff enough for the leverage for the bigger boats and engines. However they do fine on smaller boats and engines. I would try those and I suspect that they will do very well. For the 150 hp engines, I would not consider the plastic foils.
 
I should also mention that we had a Stingray foil on a previous 21 footer with a Yamaha Saltwater Series 250 hp V6, and it really improved the performance. No problems with that big beast either. The Stingray is one of the "plastic" types. I liked it so much I installed one on our CD.
 
I have had the sport SE on Litl' Tug for about a month now and I really notice the difference with it. Pluses to me include cosmetic (it matches Yamaha color exactly), ease of installation, less profile to walk around when the boat is in my driveway, cost.

It's "disadvantage" to me is that it can't be used as a step as people say the permatrim can, though I'm not sure I'd feel good about that anyway. Just from the feel of the plastic and past experience with lawn tools and kids toys made out of this kind of plastic, I do think that it will have a life span being subjected to water and sun, but with the cost and ease of replaceplacement, I am not too worried. I think I'll get many engine hours out if before it dies.
 
Ran Captain's Cat yesterday in the bay. The new permatrims on the Suzi 115's make a big difference. It's easier to hold the bow down in the chop and it gets up on plane a lot quicker. No noticible top speed reduction.

Also lets me plane at lower speeds, now around 15 knots vice the old 18 knots. All in all, a great addition.



Permatrims_on_Suzis.sized.jpg

Charlie
 
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