I need more stern lift on a twin 250 whaler. She could use a proper whaler drive/ full floatation extension to keep the nose down but that's a bit of a project. First I'll explore the hydrofoil route. So, is one foil better than another? Designs vary somewhat. Has anyone tried both a SE Sport 400 (harbour chandler sells them), vs any of the other modern foils? Any insight welcome.
School me on Hydrofoils
- Thread starter seabeyond
- Start date
Corey_lax
Crew Member
First of all, what props do you have?
Different Prop options can provide stern lift.
kaelc
Well-Known Member
I've run the 300 and 400. I was expecting more. Getting the right prop had the biggest difference for my first boat. Between the prop and the hydrofoil it fixed proposing and getting up on plane, as well as top speed. I didn't really have any problems to correct with my current boat with the 400, just bought into the hype that others thought it had improved their same model boat. A hydrofoil made a real difference in getting on a plane for my brother's alluminum hull inflatable and Yami 6hp. I'd get on the Whaler forums and get an idea of what other owners are running for prop and engine height. Maybe take a picture of your engines and transom and share them with some of the more knowledgeable people here? My feeling is the smaller the boat that is a little under power the more impact a hydrofoil will have but I'm not basing that on a ton of knowledge.
Pineapple Express
Well-Known Member
I cringe at these foil things. Occasionally there's a boat/motor combination that this helps but more often than not it's just added drag and masking an issue that should've been fixed with proper setup.
What props are you running? Do you have trim tabs (or flow interceptors ie zipwake)? How is your weight distribution...can you shift some weight forward (batteries, cooler, etc). Are your engines mounted at the correct height?
What props are you running? Do you have trim tabs (or flow interceptors ie zipwake)? How is your weight distribution...can you shift some weight forward (batteries, cooler, etc). Are your engines mounted at the correct height?
4 BLADE SS Solas. They leave something to be desired but should offer reasonable stern lift. I didn't want to cough up another 3k on props this season as those engines might migrate to another boat. I plan to try my 18p eco enertia props (have those on another boat of similar volume) to see how the boat reacts. The ecos are a lifting prop but so is a 4 blade Solas. I bet the eco enertia props weigh 50% more than the Solas which is interesting. I suspect there's a reason the merc props are 2.5X the money.
I agree with your statement. The issue is the pod is poorly designed for the hull. So yes, it's a patch job trying to avoid the 10k job of changing out the pod.
I will try tossing 300lbs forward and see what that does. My season is slowing down so I have time to play with the above suggestions over the next couple weeks.
I do suspect a pair of 400s will have a positive effect.
Pineapple Express
Well-Known Member
That's fair. And I see your point about trying $500 of foils vs vastly more expensive options.
What exact Solas prop model are you using?
FYI on my boat (23ft centre console with Yamaha F250) I switched from a Yamaha SWS prop to a Mercury EnertiaECO prop this year. The EnertiaECO lifts the whole boat up and the boat rides better in the chop, along with being more fuel efficient at cruise. I did lose 1 knot of top speed but that's not important for me around these waters. I'm very impressed with the EnertiaECO.
SpringVelocity
Crew Member
I use a hydrofoil on my boat. It's podded, and sorry they do work as a cheap solution.
The hydrofoil will fix the situation, and I also suggest getting trim tabs (sure you have them already). I would also look at if you can shift some weight forward.
Before you do anything anything look at the weight thing first. I put all my weights /anchor etc for forward as possible. Also depending on where your tanks are on boat can also affect things as well.
And no not one hydrofoil is really better than another. THE SE 400 you don't have to drill anything....
The hydrofoil will fix the situation, and I also suggest getting trim tabs (sure you have them already). I would also look at if you can shift some weight forward.
Before you do anything anything look at the weight thing first. I put all my weights /anchor etc for forward as possible. Also depending on where your tanks are on boat can also affect things as well.
And no not one hydrofoil is really better than another. THE SE 400 you don't have to drill anything....
Believe they are Rubex HR4 props.
I am also impressed with the ecos. I've run them for 4 years and they have been great. A handful of guides in different parts of the coast have had issues with them throwing an ear but I have been fortunate to not experience this. Not just once either, it's been a common occurrence and they have gone back to the Enertia.
Thanks.
Which foil do you use? Main ask of this thread was is one foil better than another. Sounds like the SE 400 is what guys use. I suspect that's mostly because it's what's available locally.
SpringVelocity
Crew Member
SE 400
Aquaholic
Crew Member
The choice (SE 300 or 400) is based on horsepower if you use the SE brand. Bass Pro has them.
I lost about 1-1.5 mph with the Mercury Spitfire 4 blade but it changed the boat characteristics so much for the better.
Looks like I'll go this way. $350 is a relatively inexpensive test.
I'll start With switching to the 18p ecos I have on hand. Then I'll add the foils if necessary (I expect it will be). Then I'll pop the Rubex back on there.
Right on. Appreciate the feedback. Top end is pretty much irrelevant for me anyhow. Boat does 50mph. If it only does 45 I could care less. I never want it doing more than 35. I'm after mid range, economy, and getting and keeping it on step better.
Aquaholic
Crew Member
I find the fear of drilling holes in the main to be perplexing because everyone seems to do it with their kicker.
Whole in the Water
Well-Known Member
The Doel Fin hydrofoil works well for me (20ft podded Silver Streak with 130 Honda & no trim tabs) and is inexpensive
It also work great as a partial prop protector for fishing & downrigger lines (saved me a few times).
It also work great as a partial prop protector for fishing & downrigger lines (saved me a few times).
SpringVelocity
Crew Member
Until you install one....
Max123
Well-Known Member
Just to throw this out there - how confident are you in your outboard mounting height?
I've been down this road on two vastly different boats. First boat I owned was a little Lifetimer with a 40hp Suzuki. The first ride was a huge diasappointment - bow was way up in the air, wouldn't plane at low speed, lots of spray off the motor - literally felt like I was dragging something through the water. Let me tell you - I was bummed, having just spend $25k on a custom built boat, and the builder is a ferry ride away. Anyway, It took it to a local shop - first thing they did was suggest the hydrofoil. Totally wrong move. It didn't solve anything - and created even more drag.
Then I started reading about how to mount an outboard correctly...
Long story short, outboard went up 2 holes (one hole at a time - lifted it myself using the trailer jack method), and added 2" of pitch to the prop. Boat flattened out beautifully, planed easier and at a lower speed, easily gained 5 mph, better fuel economy, better handling, etc, etc. Totally transformed the boat from a big old pig, to the nimble/delightful little boat I wanted. I fixed this by reading and doing the work - the shops were no help and just wanted to sell me stuff rather than put in the time. Shops feel like you want 'things' when what you really want is expertise. The only thing I was unhappy with was the fact that I'd caved by adding the hydrofoil and had drilled up my new Suzuki. The hydrofoil actually did have some benefits - the Lifetimer was a small boat and the foil actually stabilizes it quite a bit at speed - but that's not really going to happen on a big boat.
Fast forward to my second boat. 20ft Jasper centre console with an XL/25" 135 Evinrude. Boat already had 4 years and 150hrs under its belt, so you would think that the setup was dialed in. Absolutely was not dialed in - bow reared up so much before getting onto plane that it was almost scary if the weight balance was off, porpoised all over the place and zero ability to trim the engine at speed. This time I knew what to do: in the end the engine went up 3 holes to the very top mounting point. I still have the same prop on it, but could easily go up 1-2" pitch. Totally flattened out the porpoising - better fuel economy, vastly improved handling - just 'feels' nimble on its toes and fast. Thankfully never added the hydrofoil. Did everything myself - lifted the big Evinrude using the trailer jack method.
I say this with all respect: boat building is not the same as boat commissioning - two separate skills. Most outboards are mounted too low because its the conservative choice and lots of people won't know any better. You only really know a poorly rigged boat if you've experienced a totally dialed in boat. An outboard needs to be sea trialed with the boat loaded up the way you want it. First you adjust the engine mounting (one hole at a time). Only after the engine is mounted correctly can you proceed to step 2: experimenting with prop pitch / style. Playing with props before dialling in the mounting height is a great way to waste your money. Once you've done all of that - move some weight around. Only after that, and the boat is totally dialed should you start playing with tabs and foils. Tabs/foils just hide an underlying problem and kill efficiency.
Twin 250s...I suspect its beyond you to lift it in your driveway. What you can do to help out the shop (and prove that you have a problem): Take the boat out for a fast cruise on flat water with a buddy. Get them to hold the helm steady at speed, say 25-30mph (doesn't need to be flat out - just a comfortable fast cruise) with the motor trimmed as best you can. Go to the transom and take a video of the outboards so that you can see the side / rear - you need a clear shot of how water passes around the lower units. If the anti-cavitation plate isn't skimming the surface of the water - bam that's your problem, full stop. You cannot assess how a boat handles/performs when the outboards aren't mounted correctly. Don't start drilling holes for those foils until you get it mounted right. Once you have the video, you can show it to the mechanic. This can help them when they are assessing. Ideally you only want to lift the engines once - but be prepared to do it two time to get it properly dialed in.
I've been down this road on two vastly different boats. First boat I owned was a little Lifetimer with a 40hp Suzuki. The first ride was a huge diasappointment - bow was way up in the air, wouldn't plane at low speed, lots of spray off the motor - literally felt like I was dragging something through the water. Let me tell you - I was bummed, having just spend $25k on a custom built boat, and the builder is a ferry ride away. Anyway, It took it to a local shop - first thing they did was suggest the hydrofoil. Totally wrong move. It didn't solve anything - and created even more drag.
Then I started reading about how to mount an outboard correctly...
Long story short, outboard went up 2 holes (one hole at a time - lifted it myself using the trailer jack method), and added 2" of pitch to the prop. Boat flattened out beautifully, planed easier and at a lower speed, easily gained 5 mph, better fuel economy, better handling, etc, etc. Totally transformed the boat from a big old pig, to the nimble/delightful little boat I wanted. I fixed this by reading and doing the work - the shops were no help and just wanted to sell me stuff rather than put in the time. Shops feel like you want 'things' when what you really want is expertise. The only thing I was unhappy with was the fact that I'd caved by adding the hydrofoil and had drilled up my new Suzuki. The hydrofoil actually did have some benefits - the Lifetimer was a small boat and the foil actually stabilizes it quite a bit at speed - but that's not really going to happen on a big boat.
Fast forward to my second boat. 20ft Jasper centre console with an XL/25" 135 Evinrude. Boat already had 4 years and 150hrs under its belt, so you would think that the setup was dialed in. Absolutely was not dialed in - bow reared up so much before getting onto plane that it was almost scary if the weight balance was off, porpoised all over the place and zero ability to trim the engine at speed. This time I knew what to do: in the end the engine went up 3 holes to the very top mounting point. I still have the same prop on it, but could easily go up 1-2" pitch. Totally flattened out the porpoising - better fuel economy, vastly improved handling - just 'feels' nimble on its toes and fast. Thankfully never added the hydrofoil. Did everything myself - lifted the big Evinrude using the trailer jack method.
I say this with all respect: boat building is not the same as boat commissioning - two separate skills. Most outboards are mounted too low because its the conservative choice and lots of people won't know any better. You only really know a poorly rigged boat if you've experienced a totally dialed in boat. An outboard needs to be sea trialed with the boat loaded up the way you want it. First you adjust the engine mounting (one hole at a time). Only after the engine is mounted correctly can you proceed to step 2: experimenting with prop pitch / style. Playing with props before dialling in the mounting height is a great way to waste your money. Once you've done all of that - move some weight around. Only after that, and the boat is totally dialed should you start playing with tabs and foils. Tabs/foils just hide an underlying problem and kill efficiency.
Twin 250s...I suspect its beyond you to lift it in your driveway. What you can do to help out the shop (and prove that you have a problem): Take the boat out for a fast cruise on flat water with a buddy. Get them to hold the helm steady at speed, say 25-30mph (doesn't need to be flat out - just a comfortable fast cruise) with the motor trimmed as best you can. Go to the transom and take a video of the outboards so that you can see the side / rear - you need a clear shot of how water passes around the lower units. If the anti-cavitation plate isn't skimming the surface of the water - bam that's your problem, full stop. You cannot assess how a boat handles/performs when the outboards aren't mounted correctly. Don't start drilling holes for those foils until you get it mounted right. Once you have the video, you can show it to the mechanic. This can help them when they are assessing. Ideally you only want to lift the engines once - but be prepared to do it two time to get it properly dialed in.
Last edited: