hydrofoil for my 73 115 hp Johnson

[teslaman]

Would a hydrofoil increase performance for my 1973 115hp Johnson? It seems that a hydrofoil would add drag, thereby reducing my speed at WOT.

 

[steelespike]

Re: hydrofoil for my 73 115 hp Johnson

A hydrofoil should be considered a last ditch modification to improve hole shot ,handling and improve the ability to stay on plane at lower speed.It will however reduce top speed.Check my post over in the Tohatsu forum (25 Tohatsu)For some tips on no cost speed improvement.While the procedure may differ on a larger motor the results would be on par.
I have had good luck with Doelfins on to very fifferent boats but would reccomend something like smart tabs over any foil.

 

[WillyBWright]

Re: hydrofoil for my 73 115 hp Johnson

The only applications where tails don't slow you down are on flat bottom boats where you can set the antiventilation plate just above the bottom of the hull. That way they lift you out of the water then come out of the water on plane. The best options for holeshot improvement on your boat involves a lower pitch prop or a ventilated prop. Power trim is also great, but not much of a possibility for your motor or mine (which is of similar size and vintage). Trim tabs wouldn't help enough to justify the cost, but might be worthwhile if there are other considerations such as listing to one side or porpoising.

 

[teslaman]

Re: hydrofoil for my 73 115 hp Johnson

Thanks for the info, my boat doesn't seem to have any major syabilization issues or problems getting on plane so a hydrofoil really isn't necessay I guess.