does the size of a hydrofoil/fin matter

[wkend warrior]

I want to install a hydrofoil on my 25hp Johnson to help it plane. A friend of mine give me one off his 50hp but it is a lot longer than the ones I have been looking at online. just wondering if I can use it or if there are different sizes in relation to hp.

 

[rallyart]

More lift and so more drag with the bigger fin. That's about it.
The over 50hp one is what you would put on a 200 also. If you think of that weight difference you can see why there is a smaller version also.
Free is great so try it and see if you want it or not. Maybe you'll like it but decide a smaller one would be better, but you have the right way to start, I think.

 

[smokeonthewater]

The size absolutely matters... The smaller motor needs the fun that fits it right... The big one is the wrong one...