Does a hydrofoil improve performance in small outboard application?

[scipper77]

Re: Does a hydrofoil improve performance in small outboard application?

As far as the boat not planing. I would definitely try throwing a #50 sand bag in the tip of the bow. I'm not saying making your boat heavier is the right solution but for minimal effort you will see if weight distribution is part of the problem with planing out. You might just be underpowered. My 5.5hp will not plane out my 12'er under any circumstances. Adding ballast in the bow holds the tip down at speed but I wouldn't say it is on plane by any means. I primarily do it because it makes the boat much more stable and safe to operate.

I would focus on distributing the weight so that the boat is stable when you are casting and some cabin cruiser challenges you with a hefty wake. A 14 foot boat with a 9.9 will never be fast but should be reasonably stable when operated within it's limits.

 

[smokeonthewater]

Re: Does a hydrofoil improve performance in small outboard application?

consider moving MORE weight forward... can the battery go further forward? fuel tank, etc

when you rebuild your transom, look into building it as high in the center as you need for your motor and then skin it with aluminum sheet to make it pretty

 

[Jerry_NJ]

Re: Does a hydrofoil improve performance in small outboard application?

Thanks, I've always been a "low power" guy and and a small boat too... but my experience told the there was something wrong with the new (to me) Discovery 14', with a long (too long) shaft Yamaha 9.9 HP. As I may have said above I think it will now plan if that is indicated by a center crown to the prop back wash that produces its own wake and peaks up about 10' behind the boat (real guess/est on that number). It water behind the transom also has distinct flat water coming out either side of the keel. All this is good signs I think and clearly better than before I raised the engine.

I plan to put my 40 pound thrust trolling motor on the bow (home made mounting arrangement and the motor is a stern mount with the handle turned around 180 degrees) and the 50 AH deep cycle battery along with it. Together that's add about 75 or 80 pounds up front and I bet will bring the bow down some. Of course when I'm fishing off the bow using my raised chair there's plenty of weight up front but only the electric motor is running and usually in one of the lower-half speeds. No planing going on there : )

The boat is in good looking shape, the soft transom notwithstanding, so I'd like to keep it pretty.. finding construction aluminum is a problem. Of course I have the damaged first boat (Grumman 14') which has lots of aluminum if I want to learn how to cut it up.

 

[64osby]

Re: Does a hydrofoil improve performance in small outboard application?

Replace the transom this winter.

Place an add on CL to trade long shaft for a short.

If no takers use the Grumman transom skin and cap (with wood) to add height to the Discovery transom.

Use the existing holes if there are some to fasten the transom riser.

My .02

 

[Jerry_NJ]

Re: Does a hydrofoil improve performance in small outboard application?

Thanks, I have a short shaft Evenrude 9.9 HP on my bent Grumman.. the Discovery has a long shaft transom. So "why is the long shaft engine too long"? Go figure. Maybe that's why Discovery went out of business about 15 years ago.. Yamaha is still in business making long shaft engines.

 

[smokeonthewater]

Re: Does a hydrofoil improve performance in small outboard application?

I think you need to hang your short shaft engine on there and take a couple pics..... take her out n give her a try