School me on Hydrofoils

[searun]

Super glad to see the hydrofoil corrected your pod stability issues, and as I also found provides increased trim adjustment even at lower speeds. Way better solution than putting weight in the bow to overcome the transom imbalance that creates the porpoising and lack of trim adjustment.

 

[Pineapple Express]

This post caught my eye, despite my boat getting on plane quickly and not having bow-high trim issues. What piqued my interest was @seabeyond can now stay on plane all the way down to 14 kn. My hull drops off plane around 16-17 kn and plows along bow up, thirstiest rpm range other than WOT. My transom has this weird layout and I don't see any room for trim tabs, but a hydrofoil might be worth trying. Not a big cash commitment, and easy to remove if not helping.

Technically @seabeyond posted speeds in MPH, not knots. But that means his planing speed is even better than you think since 14 MPH = 12.2 knots.

 

[Aquaholic]

Update:

Installed the se400 foils and took it for a test run in ideal conditions last weekend.

What a game changer for this boat. It's like an entirely different machine, in calm water anyways. Rides much flater, gets on step considerably quicker, and holds plane down to 14mph. 20% increase in mpg through the 16-23 mph range and still reaches 50 at wot. These did everything I had hoped for thus far.

I'm curious how it preforms under normal load (It was only me on board with 100 gal in the tank) and in typical conditions. I'll have to get it out again before I pull it for the winter.

A note that the no drill option really doesn't work on the 8" wide cav plate of the V8 merc. It only species a Honda and the 350 yam as needing modifications but I suspect the literature hasn't been updated since prior to the merc 2018 v8 introduction. Instal was a pain for the no drill option. I doubt it'll stay on there long term so I'll drill them on there now that I see they work. Not a big fan of drilling holes in these cav plates but it is what it is.

I will try a prop swap to the eco enertia 18 as I am suspicious this hull can get better mid range economy than it currently does. Whether it's worth the 3k in props and hub kit is debatable. I guess I'll get a better idea of the potential pay off when I swap the props and give it a test run.

Thanks for the feedback on the thread fellas.

Driveability is what I noticed too. The low speed planing ability at much less rpm than before is really noticeable, one of the best improvements. Ease of getting on plane is also a huge difference, and hardly any deep v wander at low speeds while navigating False Creek At 4-5 mph. Caveat: I did also add a 4 blade, but the foil already transformed the boat.

 

[BC Coast Pilot]

Try a stern lifting prop like a Mercury REV 4 (four blades) certainly more lift than my ECO Enertias
I have a set in 17p as spares if you still need to try for some lift without foils. I try to avoid drilling or exposing any aluminum on an outboard as you're basically creating an area for electrolosis. If you do, certainly prime and paint the areas and monitor.

 

[Aquaholic]

Try a stern lifting prop like a Mercury REV 4 (four blades) certainly more lift than my ECO Enertias
I have a set in 17p as spares if you still need to try for some lift without foils. I try to avoid drilling or exposing any aluminum on an outboard as you're basically creating an area for electrolosis. If you do, certainly prime and paint the areas and monitor.

Mercury is the leader in props. I used a Spitfire 4 blade, it is aluminum but still in the $400 range.

 

[Max123]

Really interesting to read. Even with my outboard mounted at the correct height, I still get a nagging porpoising effect if I try to trim out much at Cruising speed (22-30mph). It completely goes away at +35mph when the hull is more out of the water, but below 30mph I have very little trim adjustment.

I'm currently running a 15x15p Evinrude TBX SSP - which is I believe is their general purpose/neutral stainless prop.

I've wanted to avoid the hydrofoil, and would be interested in trying a different prop. Ideally jump up to a 17P prop to get a little more speed and stick with an Evinrude prop, so I don't need to mess around with different hubs. Any recommendations? Cyclone is listed as stern lift - maybe Rebel? Alternatively, it seems like the Mercury Enertia Eco props are fairly universally well regarded and provide some stern lift - Rev4 a little more stern lift as well. Just need to figure out the hub and if these props fit an M2 gearcase.

Any good local sources in Vancouver that let you test?

 

[Aquaholic]

Really interesting to read. Even with my outboard mounted at the correct height, I still get a nagging porpoising effect if I try to trim out much at Cruising speed (22-30mph). It completely goes away at +35mph when the hull is more out of the water, but below 30mph I have very little trim adjustment.

I'm currently running a 15x15p Evinrude TBX SSP - which is I believe is their general purpose/neutral stainless prop.

I've wanted to avoid the hydrofoil, and would be interested in trying a different prop. Ideally an 17P Evinrude prop, so I don't need to mess around with different hubs. Any recommendations? Cyclone is listed as stern lift. Alternatively, it seems like the Mercury Enertia Eco props are fairly universally well regarded and provide some stern lift - Rev4 a little more stern lift as well.

Any good local sources in Vancouver that let you test?

My lease return engine that I bought from Bridgeview had warranty remaining, and their shop did not hesitate to put the SE300 foil on it that was on the engine I traded in. Point being is I think some are over thinking the 4 holes in the cavitation plate on engines with zinc's in place, and usually tilted out of the water when not in use.

 

[Rayvon]

I went with a Solas 4 blade because I already had a prop with the hub kit for Suzuki,but I'm still fine tuning and need to go up to 19P from 17P.
What other brands of props can fit suzuki 200 with the proper hub kit?

 

[seabeyond]

Really interesting to read. Even with my outboard mounted at the correct height, I still get a nagging porpoising effect if I try to trim out much at Cruising speed (22-30mph). It completely goes away at +35mph when the hull is more out of the water, but below 30mph I have very little trim adjustment.

I'm currently running a 15x15p Evinrude TBX SSP - which is I believe is their general purpose/neutral stainless prop.

I've wanted to avoid the hydrofoil, and would be interested in trying a different prop. Ideally jump up to a 17P prop to get a little more speed and stick with an Evinrude prop, so I don't need to mess around with different hubs. Any recommendations? Cyclone is listed as stern lift - maybe Rebel? Alternatively, it seems like the Mercury Enertia Eco props are fairly universally well regarded and provide some stern lift - Rev4 a little more stern lift as well. Just need to figure out the hub and if these props fit an M2 gearcase.

Any good local sources in Vancouver that let you test?

The eco is a 16 Dia and very heavy. I have 4 blade solas rubex props on that boat now. The ecos I have on the other merc set are 50% heavier I'd bet (the weight difference is evident when you switch into gear). They also have a big surface area relative to props like a regular enertia. 17p is the lowest pitch they offer which might be more like jumping from 15p to 18p. I'd definitely trial a pair prior to shelling out the cash.

 

[Max123]

The eco is a 16 Dia and very heavy. I have 4 blade solas rubex props on that boat now. The ecos I have on the other merc set are 50% heavier I'd bet (the weight difference is evident when you switch into gear). They also have a big surface area relative to props like a regular enertia. 17p is the lowest pitch they offer which might be more like jumping from 15p to 18p. I'd definitely trial a pair prior to shelling out the cash.

I was doing a bit of research and my gearcase will only fit up to 15-3/4" diameter. Probably looking out for a standard Enertia (which is smaller diameter, but doesn't seem to have quite the same magic as the ECO - or maybe a Rebel). I suspect 17P may be too much for me - would be great on a calm day with a light load, but with a bunch of people and gear, the lower gearing is just fine. Will maybe hunt for a 15P or 16P to try out. The cost of experimenting with props is just stupid.

 

[trophywife]

i have put one on every boat i owned. never found a detriment to them. only improvements.