To Use or Not Use Hydrofoil Fins

[sir-vivor]

I have a 21' Striper 2100WA with a 200HP Ocean Pro, last week I broke my left side Hydro Fin and before replacing it I wanted to see how my boat would react with out them using only the trim tabs, so I took the broken fin off and the other.

Just to let you know my boat weighs about 3500lbs and I have a set of Bennet Sport Tabs.

I have always had hydros on my engines but never had trim tabs but I got to say when I took the hydros off and just used the trim tabs I noticed ;

- The boat was faster out of the hole
- Turning was much sharper
- I got better reaction from the trim tabs


I WILL NOT BE REPLACING THE HYDRO FINS.


Clint

 

[Lipripper]

I have only taken them off boats..... I believe in weight distribution

 

[Marsman]

Trim tabs all the way. I took my hydro off also.

 

[dawn2dusk]

interestin...I have a 19ft striper and same thing broke one so took them off. I found everything to be better as well.

 

[Sharphooks]

Most mechanics I've talked to quietly say that outboard engines were not designed to have those fins attached to the lower units and to steer clear of them.
I use them only in the smaller sizes ( 5 - 15 Hp outboards) for my inflatables. They do help in shallow-water (river running) conditions to get on plane quick and to keep you there. In the larger Hp, I stick with trim tabs

 

[NautiGirl]

I think trim tabs get the job done better and adding the hydro's are like wearing a belt and suspenders. If you don't have trim tabs, then the hydros can be a great addition. I don't have the trim tabs and the hydro's make a huge difference with my lower horsepower boat.

 

[Hookin'up]

Thanks for the report Clint,
in that case think I'll just stick with the Bennett m120's

 

[Lipripper]

Most mechanics I've talked to quietly say that outboard engines were not designed to have those fins attached to the lower units and to steer clear of them.

Heard that they cause the cavitation plate to crack on most stern drives as well. It is like a black box..... a band aid solution to a bigger problem

 

[burnsy22]

I don't know about the caivation plate cracking, I think with all things there can be horror stories. I have twin 50's on my 17 foot Arima and there is no where to put trim tabs or smart tabs. So I am giving the SE 200's a whirl as hydrofoils. I will let you know if they help on planing which is the issue I have. WIth twin engines , the gas tank , twin batteries and down riggers all right at the stern my boat struggles on getting out of the hole. Twin 50's wouldn't have been my first choice, though they aren't bad at all really, I am hoping these foils help out off the start.

Will let you know my results.

 

[sir-vivor]

Hey burnsy22 are our 50's turning in the opposite direction of each other or the same ?

Interested in knowing how the foils work for you , I would think you will get up on plane quicker but trust me I have been soooooooo wrong before LOL

Let us know for sure !

 

[burnsy22]

They are counter rotating

 

[Bifmalibu]

Will your Arima plane with just one of those 50's? Good safety factor there.

 

[burnsy22]

Yeah it wouldn't before I put the foils on...So I am interestested to see if it will now with them on....Details to follow. Hopefully will be out Sunday.

 

[Clipper]

I used a hydrofoil on a previous boat to help with a porpoising issue, which it did but they really are just compensating for other problems like under power, engine height placement, bad boat balance and like that. I haven't needed to use them on any other boat since then and would look for the underlying problem before going that route. They do work but it's really a last resort, IMHO.

 

[trendsetter]

I used a hydrofoil on a previous boat to help with a porpoising issue, which it did but they really are just compensating for other problems like under power, engine height placement, bad boat balance and like that. I haven't needed to use them on any other boat since then and would look for the underlying problem before going that route. They do work but it's really a last resort, IMHO.

X2 on what clipper said.

 

[ripper12]

trim tabs

put 120 bennetts on 21 trophy what a diff' should have done sonner instead of thehydro f. if you install your self recomend 1/2 inch not 1/4 from bottom.watch you don,t snap screw heads see you on west coastaug 19.

 

[fishies]

I have a 16ft fiberglass with a 50hp with hydrofoil fins...its a bit slow out of the hole but its all I know because I haven't owned another boat with or without the fins. Not sure on the weight of the boat but its not much. Gas tank up front. Cruises at 20-22mph at around 3/4 throttle/4800 rpm. Do you think these are helping me or hindering other performances? Would you guys stick with them or ditch them?

 

[burnsy22]

My first trial of the my hydrofoils on the twin engines went well. It definitely helped get the boat on plane and also stay on plane at a lower speed. Forgot to try and get the boat on plane with just one engine as I couldnt do it before...Will let you know how it works out. Also it seemed to not effect my speeds at all being cruising or top end.