Outboard hydrofoil / fins

[Blankton]

It arrived from Australia and I fitted it. Not the best job, but I had the missus eyes burning into the back of my head at the boat launch ramp



It has made a big difference. Now the boat climbs easily onto the plane every time when I am by myself. It wasn't so much of a problem 2 up before, because one would go in the bow anyway.

Top speed achieved was 19kts, I've had 21 before, but I had some tide with me that day, so I don't have enough information to judge whether I lost any speed or not yet.


To address some of the other questions. This is how I tend to set up if by myself. The fuel tank is clipped to some extra D rings I fitted. It could perhaps go a bit further forward, but that makes it difficult stepping into the bow. The anchor is in the smaller grey box that goes right up in the bow before the tank.






Other than myself and the engine (and its new hydrafoil ) there isn't any weight in the rear 50% of the boat.

If I have a passenger, the fuel tank can clip into some further back D rings and the anchor sits back with me, to allow them to sit in the bow or on the front seat.

[Limecc]

Originally Posted by Blankton

It arrived from Australia and I fitted it.

Quite a nice looking one and colour-coded

Does it lower your planing speed as predicted and have you experimented getting the engine height optimal? Can you mount the engine higher now without prop ventilation?

I'd like to try one on my 3.5 Tohatsu which is making such great power with the 5hp carb that the standard mini sized AV plate isn't doing a very good job.

[Blankton]

Originally Posted by Limecc

Quite a nice looking one and colour-coded

Does it lower your planing speed as predicted and have you experimented getting the engine height optimal? Can you mount the engine higher now without prop ventilation?

I'd like to try one on my 3.5 Tohatsu which is making such great power with the 5hp carb that the standard mini sized AV plate isn't doing a very good job.

yes, I feel it has lowered the planing speed. With a bit of messing with the balance we could plane at about 9knts, which I think is ok for my 8knt speed limit . It seemed to climb more gently onto the plane as well, rather than being all or nothing.

I did notice when going through some chop at planing speed it felt a bit like the back end was being pulled down, when perhaps before it would have been wanting to jump out of the water. Maybe this is one of the bad characteristics that people describe (perhaps if you were fast cornering it would be more concerning) but for my purposes the boat feels a lot more useable.

As I said in an earlier post, the "window" for getting on the plane has been increased (with respect to the many variables e.g. weight distribution, sea conditions, throttle % etc).

I've had another look at transom height, I'm 2" below, which should be ok according to the literature. There is very little availability for raising the height due to the relatively low reach of the brackets on the engine and the position of the grip plate thingy (whatever it is called). I will try 1/2" of my HDPE left from the seat next time I'm out, but any more than this I will have to remove and re-fit the grip plate thingy and any more than 1", would need some kind of structural extension to the transom.

[Fenlander]

Looks like you've found the result you wanted... excellent.... and neat looking too.