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coyote3
02-07-2004, 03:12 PM
recently i posted a question about trouble getting my boat on the plane. one of the replies delt with the addition of a small hydrofoil to the motor.this is the second piece of advice along this line ,the first was from (solas) but a mate poured cold water on the idea,said it would not work..any feed back would be appreciated ..thanks guys.. ???

flytime
02-07-2004, 03:42 PM
Hi coyote3,
I just brought a 4.45 hornet. It had no foil on it and it wasn't comming out of the water as it should. I put a SE 200 hydrofoil on it and it jumped out of the water. definetly the best thing i've added to the boat.
Steve :)

coyote3
02-07-2004, 04:14 PM
thanks steve

bigbrian47
02-07-2004, 05:44 PM
see if you can contact someone with the same rig as yours
foils are wonderful on some rigs dangerous on others
cheers brian

aussiebasser
02-07-2004, 06:22 PM
I don't know what hull/motor set-up you have, but some care needs to be taken when choosing a foil.
In my experience the SE Sport and Permatrim are helpful in hole shot speed, and have a less detrimental effect on top speed.
If you have a flat bottom boat be very careful if fitting a Stingray. These can produce too much stern lift at speed, and cause broaching. We cured ours by cutting the back 50mm off the Stingray to get rid of the down turn on the trailing edge.
Another couple of benefits of fitting a foil are a much better transition when coming off the plane, the @rse doesn't sink down as much, and better fore/aft stability at rest.

Cloud_9
02-07-2004, 06:37 PM
foils are also good for getting a good low speed plane ( lowest rev posible and still keep on the plane ).
thinking of fitting 1 to my 9.9 mariner well its been played with so its more like a 15hp but want to stop bum drag at low speeds.
you can make your own out of ally the hire boat places dont buy the foils they make them.


Cheers Cloud 9

ali
02-07-2004, 09:01 PM
Do IT coyote3 , DO IT! I put a permatrim on my last boat ,[quintrex 5.2m cuddy /70hp] and mate It made a huge difference to it's performance. It planed at a much lower speed and handling vastly improved.I'ts the first thing I'll put on my next boat [hopefully a 6m yalta , if I can find one.]GO FOR IT!!! [smiley=2thumbsup.gif] stiffrod.

McCod
02-07-2004, 11:09 PM
Are the go for most small boats and will usually use less fuel as well. Will get out of the hole quicker and plane at lower speeds.
cheers McCod.

drevil
03-07-2004, 03:42 AM
My 1990 100 merc came with a metal foil that is fairly flat but has a vent that opens towards the front of the boat. I guess the idea is that it scoops water into the prop area to help get better lift.

Anyone have any opinions on this sort of foil? Can it affect top speed? I notice that modern plastic/rubber foils are smoot and do not have any vents.

I'm thinking about taking it off and seeing what the effect is. What do you reckon?

aussiebasser
03-07-2004, 04:36 PM
Sounds like your's is a Solas drevil.

Big_Kev
04-07-2004, 01:16 AM
You can try the foil Coyote it may work in some instances, but from your original post and the weight you are putting the boat you will need the bigger motor in the long run.

Cheech
04-07-2004, 04:19 PM
My boat is quite underpowered being 4.5m and only a 35hp Johnson. Had a big foil on it when I bought it so don't know what it would be like without it but I can easily tell that it is the foil that gets the boat out of the hole and on the plane. I would probably consider "not" having one only if I had excess horsepower.

Cheech

drevil
05-07-2004, 09:35 AM
Solas eh, Aussiebasser? Is that good or bad?

coyote3
06-07-2004, 04:03 PM
be nice guys ..i posted this notice to learn a little more about foils, dont hijack the discussion with stories about solas..they were just being helpfull to a novice in the boating fraternity.. thanks for all your experience and keep it comming..

Scorpion
07-07-2004, 04:59 AM
I put foils on my boat and the performance of the boat change for the better. Quicker on the plain, less revs to get on the plainand it also helps when the boat is overloaded.

Scorpion

drevil
07-07-2004, 05:14 AM
What's your point, coyote3? How do you know that solas foils are not the ideal solution for your situation? I can't see how a topic can be hijacked if it discusses the pros & cons of a specific brand of foil. Am I missing something?

coyote3
07-07-2004, 03:16 PM
sorry guys i read it as solas drivel(as in rambling) hope you can see the funny side of this" drevil" and "aussiebasser".. sincere apolligies.. coyote3..ps didnt do real well at school.

435_Mark
07-07-2004, 06:32 PM
Something to consider is the size of the foil for the rig. I am unlucky enough to have a Hornet with a 50hp 4s Yamaha (yes one of those that porpoises). Without going in to the long and sad story the addition of an SE sport 200 did help. However, swapping to a SE sport 300 INCREASED my top end speed from 44km/hr to 55km/hr (logged by gps). It has also helped reduce the porpoising.

drevil
08-07-2004, 03:42 AM
No problem, coyote3. I read what we said and just couldn't figure it, but now it all makes sense. ;D

Burley_Boy
09-07-2004, 12:11 PM
I've got a Yammie 40 on a 4,5M fibreglass hull and am about to add the foil to it, Mark are you saying that the bigger the better?

Monza
09-07-2004, 04:30 PM
Careful with bigger foil. I had one of my 5m fibreglass boat which work well in a straight line into the waves, however in rough water at speed the size of the foil forced the motor trim hydraulics to move, and it also had a nasty habit of violently changing the direction of the boat when travelling down following seas.

435_Mark
10-07-2004, 12:36 PM
Burley Boy, Nooo I'm not saying bigger is necessarily better, what I am saying is that it was astoundingly better on my boat. I was very suprised at the difference it made. I believe this is due to the poor hull shape of these particular hornets. The point I was trying to make is that it can be very hard to get it right. The chat boards are your best bet to compare notes with someone who has the same hull as yours and to find out what the outcomes were for the different brands of foils. Good luck. P.S. The consensus seems to be that the SE sport & Permatrim foils are very good.

lurch
14-07-2004, 01:39 PM
Very interesting thoughts guys .

I dont know if anyone looked at my post on propellors but im now thinking it might be related to a foil . I have one fitted to my boat its a Nautiglass V150 with a 90 so im definately not underpowered , but it has some strange habits . Great getting out of the hole just seems to rise up evenly from stationary to planing without really lifting the bow at all, but i have alot of trouble trimming the boat once underway, it seems no matter how much trim i give the motor its very hard to lift the bow unless all weight is down the back. Also when in a following sea as Monza posted it is very sensitive to breeching ??

Just wondering if this could be due to the foil , mine is a "Stingray" brand and ive looked at the blurb on them they say that they generate lift from their shape i'm now wondering if this is the cause of my problems ?? I'm going to take it off for the next time out and see if it makes a difference and ill let u know.

What hydrofoils do everyone have on their motors (Monza what brand was it) ??

has anyone any reports on different brands ? Ive been looking at the SE Sport 300 , 435 mark does your trim work OK with yours on ??

aussiebasser
14-07-2004, 03:50 PM
I'm not knocking or supporting Solas, just saying that by the description of the foil it seems to be a Solas one. #I'd be a touch hesitant about having that much S/Steel around my alloy motor, but that's just me.
I'm compared an SE Sport 300 to a Permatrim on my 435 Hornet with 50 EFI Merc. #I'm not convinced that there is any difference. #I have had bad experiences with Stingray brand foils due to the increased lift brought about by the large downturn at the trailing edge of the foil. #Have seen a Savage 440 Jabiru and 4.1 Horizon almost undriveable because of the foil. #A jigsaw job to remove the trailing edge and the problem was solved. #Stingray charge extra for steering stabilisers, but they are built in to the SE Sport and Permatrim.
No floggin' nuthin' for nobody, just my opinions. ::)
I still don't know what your rig is to give any further feed back.

Monza
14-07-2004, 04:26 PM
I think mine was a Stingray. Removed it and problems went away. I put up with bowlift at take off now - at least it's predictable !

coyote3
15-07-2004, 02:38 PM
hey guys. i am the member who originally posted the message but did not follow through with the details of my boat because i thought the (post) had run its race..so here goes 3.8metre stacer open dingy with some false floor and casting platform,powered with a 15hp mariner top speed of a mind numbing 21 mph(by GPS)

coyote3
15-07-2004, 02:42 PM
also it dosent start to plane till 14 mph

lurch
15-07-2004, 07:20 PM
Where are you coyote3 ??

maybe you could try my stingray !!

Peter

coyote3
16-07-2004, 04:25 PM
think i am gunna bite the bullet and buy a foil , which one is the big question..thanks for the offer peter...went to permatrim.com. it seems to be a simple enough design ,sometimes simple is best..the mate that bagged the idea of a foil has already offered me a loan of his stingray but i would like to get it right the first time rather than having a series of holes in my motor

aussiebasser
16-07-2004, 04:58 PM
25 bucks should buy you a 2 piece E Z Foil in the smaller size. My nephew put one on his 15 merc 360 Quinnie set-up and it did the job.

coyote3
17-07-2004, 02:05 PM
thanks for the input ,guys