Opions Please...

[jimyoung]

Not about my spelling either.........rather about hydrofoils....ie stingray, doelfin....are they worth the effort?
And a note...I have found so much info on here, just reading other peoples threads.....experience goes along way, and it seems to be here, Thanks to all the old salts on here........

 

[ninja500r]

Re: Opions Please...

This is a topic I have done extensive research on. I have determined that as far as I can tell the fins deals you put on the motor are no good. What you want is Smart Tabs. I am going to get a set for my boat asap. Do a search for them on this forum and you will find lots of discussion.

 

[jmburock]

Re: Opions Please...

I haven't done extensive research on hydrofins/ doel fins/etc. but I can tell you from personal experience that putting on the Davis fins has helped bring the boat to plane faster and reduce bow lift out of the hole. Only cost $40 and took about 20 minutes to install. Well worth it if you don't mind a couple holes in your aluminum. My boat is a 17' Boston whaler w/ Mariner 75hp 3 cyl.

 

[Silvertip]

Re: Opions Please...

I've used both extensively and if anyone tried to make off with my Smart Tabs I'd hurt them in ways they never dreamed! Forget the fins.

 

[Awsum O]

Re: Opions Please...

A boat I had a few years back, (14 1/2' Sunray w/50hp Merc) came with the Doelfin brand hydrofoil on it. All around I didn't notice much difference with or without it. Out of the hole it seemed to keep the nose down a bit but didn't seem to plane any faster and it also didn't gain any top speed or improve pulling up water skiers and kneeboarders. I'm not saying they don't work, they just didn't make a very noticeable difference for me. At the price they are it doesn't hurt the pocketbook much, only you have to drill holes to mount them. Trim tabs are definitely the best way to go and those Smart Tabs look like they are simple to use and a very reasonable price for what you get. If you like your boat and plan on keeping it, I'd recommend the tabs.

 

[redjmp]

Re: Opions Please...

I've got a cobra style ski boat with an inline 6 and tried removing the dolefins and found that the boat did not go any faster without them. I was slower getting out of the hole and tended to not respond as well to changes in trim.
With them back on, it definately got on plane at a much lower speed and responded much better to the trim control. Mine actually ride above the water when the boat is planing so then they don't have any drag on the boat when it is trimmed out properly. They also really help to drive the nose down so that I don't porpoise at all when cruising through choppy water, that is to say when I decide to trim the motor further down than I usually would for normal calm water cruising.

 

[studlymandingo]

Re: Opions Please...

They are not worth the money; for a few bucks more you can get a set of smart tabs that will do worlds more good for your boat. The fin should be out of the water when running on plane so it won't be doing anything. Tabs continue to work to lift the stern at all speeds.​

 

[JB]

Re: Opions Please...

This is a non-repair topic. Going there.

 

[jimyoung]

Re: Opions Please...

Great responses.Thanks

 

[tashasdaddy]

Re: Opions Please...

i have 2 pair in my shed, waiting to give them to someone i don't like.

 

[sharps45]

Re: Opions Please...

Tasha- Did you get them for your Chris Craft deckboat? If so, why did you get them and why don't you like them? thanks

 

[studlymandingo]

TD...President of Boataholics Anonymous

TD...President of Boataholics Anonymous

Tasha- Did you get them for your Chris Craft deckboat? If so, why did you get them and why don't you like them? thanks

My guess for Tashasdaddy is based upon the fact that he is seriously addicted to boats, I think he has probably bought and fixed-up about 9 million in the last 2 months. When he buys a boat with hydrofoils, the first thing he does is remove them knowing that they are a starting point for getting the boat right. This is just a guess, but I will bet his reply is going to be something along these lines!​

 

[tashasdaddy]

Re: TD...President of Boataholics Anonymous

Re: TD...President of Boataholics Anonymous

Studly you got it, on the nose. my 18' center console had one, it was squirrely as heck, would throw the bow down getting out of the hole, causing it to plow before i could trim up, it would slide in corners, of cause the bow to dip to the side you were turning into. pulled them off and handled great.

like is said, i'm going to give them to someone that pissed me off.

 

[tashasdaddy]

Re: TD...President of Boataholics Anonymous

Re: TD...President of Boataholics Anonymous

just notice the change in title, i'm and addict and admit it. isn't that the first step, i don't plan on correcting it.

 

[BillP]

Re: Opions Please...

Not about my spelling either.........rather about hydrofoils....ie stingray, doelfin....are they worth the effort?
And a note...I have found so much info on here, just reading other peoples threads.....experience goes along way, and it seems to be here, Thanks to all the old salts on here........

I've been using fins for 25+ yrs (and tabs longer). They work fine on most small boats to get out of the hole flatter or to trim the motor up for faster speed without venting the prop. If you look carefully, most of the negative examples are typical results of an incorrect installation (too low) or wrong fin type. If the fin won't clear the water when on a plane don't expect stellar results. Hold the fin up to the cavitation plate and see where it rides...below the boat bottom or above it. That will tell you which direction to go for best performance. Sometimes the motor has to be raised one hole to get the fin high enough. Use vee fin Stingray types on vee bottom boats and Doelfin types on flattish bottom boats.

Be aware that adjustable trim tabs also give miserable (same as the 18' center console posted about) results if not adjusted properly and can be a pain at the launching ramp, around docks or when beaching.

bp

 

[LORDY611]

Re: Opions Please...

I used to have a 16' Whaler-type center console with a 48 Johnson, called a Lucraft out of Daytona Beach. It had a Doelfin or similar on it, and it would jump to a plane in no time. BUT it tended to plow so I had to trim it up and it could get to the point of ventilation, and then if I needed to turn, trim it down, slow down, turn, blah blah blah. I dont think the boat really benefitted, and I didnt put 2 & 2 together until reading this thread. Not sure where the cav. plate was relative to the bottom of the hull, never really paid attention. I dont plan to use one on my new rig. I'll see how she fares with the T&T and go from there.

 

[ondarvr]

Re: Opions Please...

I'm with BillP on this. I put them on my 19' CC (200 Evinrude) because when the motor is mounted high enough for the best performance, the prop would ventilate under hard acceleration or in turns. I had them in my shop for years just sitting on the bench and didn't want to spend the $$$$ on a new stainless prop for a boat I don't use very much, so it was a no cost test. It solved all the issues better than expected, although I'm sure that with a good SS prop I would have gotten even better performance, but like I said, this was no cost solution. They are not in the water at speed, so there is no adverse effect on handling and no reduction in top speed.
Used correctly they can work, but don't expect them to solve every problem on a boat with a poor set up, it would be one of the last things to try.