Super stern heavy Hewescraft, .... and rides terrible !

[Grey Ghost]

I just repowered my Sea Runner 200ET. Went from the 115 to 150 Yam....2 batteries at the stern as well as a 9.9 Yam and a 5 gallon gas can on the extended transom. My boat has a (heavy) custom hard top...forward weight...I have a lot of 'stuff' on the boat. It sits pretty level in the water. At 3800 RPM I am going 28MPH. I tried to get to WOT but jammed out.....Would be in the mid 40's...if I ever find the right sea conditions. For me, in the conditions I boat in, its nice to have that extra power in reserve but the 150 is as big a motor as I would want. I can't imagine that power and weight...on an aluminum 18' soft top.

 

[Offshore]

I have had good success with Permatrim, after I got past drilling holes. I wish I had installed it sooner. My boats top speed is 50 mph so power is not a issue. The Permatrim gives more stern lift at slow speeds and I get better fuel efficiency because I only use the trim tabs to level the boat.

 

[Rain City]

Yes they work. Unfortunately most that have never used one just scoff at them. The new ones are drill less even. Boats can porpoise even with trim tabs.

There are three things it does. It eliminates the stern slipping on tight turns. It pushes bow down/eliminates porpoising (especially podded boats), and even more so with additional trim tabs. And third it allows you to come up on plane quicker. I haven't seen any performance downsides on any of my boats.

But it will not help when boats at rest. As mentioned shift weight forward. Batteries etc.

I had one on both of my previous two boats as a fix for not enough power. They do work wonders for a boat that just isn't cutting it. What I was told though, is that they cause a lot of turbulent water around your prop which decreases efficiency and increases the frequency of prop cavitation. I also found that they made the boat a lot more reactive when turning and had few scary moments where the handling got a little screwy with a load of people on the boat. They're amazing things but I'd imagine most proffesional boat builders/mechanics would suggest that they're a "fix" but not ideal.

 

[Squire]

I had one on both of my previous two boats as a fix for not enough power. They do work wonders for a boat that just isn't cutting it. What I was told though, is that they cause a lot of turbulent water around your prop which decreases efficiency and increases the frequency of prop cavitation. I also found that they made the boat a lot more reactive when turning and had few scary moments where the handling got a little screwy with a load of people on the boat. They're amazing things but I'd imagine most proffesional boat builders/mechanics would suggest that they're a "fix" but not ideal.

I agree that their primary function is to compensate for a lack of power. I put one on an outboard two boats ago for this reason. It did not get me on plane any faster but it did help keep me on plane at lower speeds. It has been my experience that the correct prop choice for the boat and motor has a greater impact that adding a Doel Fin or other brand of Hydrofoil.
I personally wouldn’t add one to a boat that had plenty of power and trim tabs but that’s just my choice.

 

[Rain City]

I agree that their primary function is to compensate for a lack of power. I put one on an outboard two boats ago for this reason. It did not get me on plane any faster but it did help keep me on plane at lower speeds. It has been my experience that the correct prop choice for the boat and motor has a greater impact that adding a Doel Fin or other brand of Hydrofoil.
I personally wouldn’t add one to a boat that had plenty of power and trim tabs but that’s just my choice.

I agree 100%

 

[SpringVelocity]

I had one on both of my previous two boats as a fix for not enough power. They do work wonders for a boat that just isn't cutting it. What I was told though, is that they cause a lot of turbulent water around your prop which decreases efficiency and increases the frequency of prop cavitation. I also found that they made the boat a lot more reactive when turning and had few scary moments where the handling got a little screwy with a load of people on the boat. They're amazing things but I'd imagine most proffesional boat builders/mechanics would suggest that they're a "fix" but not ideal.

Mmm. Never seen an efficiency decrease myself on my boats.

Don't see how mathatically that makes sense from engineering standpoint in fluid dynamics and how hydrofoils work.

Trim tabs, 4 blade props and hydrofoils are all specific to your boat. They are all aftermarket band aids. You just choose what works for you.

Anyhow running it on my boat with tabs as well just offering on opinion. They are great for aluminum boats that size.

And for record the original poster does need to really move weight up front. That I agree.

 

[Rain City]

Mmm. Never seen an efficiency decrease myself on my boats.

Don't see how mathatically that makes sense from engineering standpoint in fluid dynamics and how hydrofoils work.

Trim tabs, 4 blade props and hydrofoils are all specific to your boat. They are all aftermarket band aids. You just choose what works for you.

Anyhow running it on my boat with tabs as well just offering on opinion. They are great for aluminum boats that size.

And for record the original poster does need to really move weight up front. That I agree.

Yeah I never saw the reduction myself either. I was just told that by a mechanic once.

 

[brutus]

Yeah I never saw the reduction myself either. I was just told that by a mechanic once.

Ok I just put this out there lol, because stirring the pot on a rainy day I like lol,if hydrofoils are a marvel of naval engineering, you would think outboard manufacturer would cast them in the lower Gear unit housing, I mean if it improves all said above they would have the best outboard in the bizz, just my twisted overthinking mind at work here boys

 

[SpringVelocity]

Ok I just put this out there lol, because stirring the pot on a rainy day I like lol,if hydrofoils are a marvel of naval engineering, you would think outboard manufacturer would cast them in the lower Gear unit housing, I mean if it improves all said above they would have the best outboard in the bizz, just my twisted overthinking mind at work here boys

I guess they could outfit them all with 4 blade props as well lolololol

Clown

 

[Aquaholic]

Ok I just put this out there lol, because stirring the pot on a rainy day I like lol,if hydrofoils are a marvel of naval engineering, you would think outboard manufacturer would cast them in the lower Gear unit housing, I mean if it improves all said above they would have the best outboard in the bizz, just my twisted overthinking mind at work here boys

All boats would come from the manufacturer with trim tabs as well, based on that line of thought, but they do not.

 

[Rain City]

Can't we all just get along.

 

[wildmanyeah]

They want to advertise the boats as cheap as possible and then have you walk out with 20k worth of extras lol

 

[SpringVelocity]

Can't we all just get along.

NO LOL

 

[Rain City]

They want to advertise the boats as cheap as possible and then have you walk out with 20k worth of extras lol

Yeah I don't see trim tabs being any different than adding 4x4 to a truck. Obviously all REAL trucks have 4x4 but they'll sell you one without . Tabs are a no brainer for increased performance and stability IMO.

 

[Squire]

Yeah I don't see trim tabs being any different than adding 4x4 to a truck. Obviously all REAL trucks have 4x4 but they'll sell you one without . Tabs are a no brainer for increased performance and stability IMO.

Tabs keep me from being that guy who asks the overweight guest to switch sides with the slim guest so I can run level.

 

[brutus]

NO LOL

It is raining after all

 

[SpringVelocity]

Tabs keep me from being that guy who asks the overweight guest to switch sides with the slim guest so I can run level.

OMG lol

 

[brutus]

Can't we all just get along.

That would be boring lol

 

[Charter Tofino]

The 4-5 aluminums under 20 feet that I’ve owned have always seen better performance with a hydrofoil. The hulls are so light that they rarely come close to being balanced after you slap 4 strokes on. The foil helps the ride in chop by holding the nose down and helps get on step easier. I wish more builders would address this and move fuel tanks and batteries forward.

 

[TinnyTime]

The 4-5 aluminums under 20 feet that I’ve owned have always seen better performance with a hydrofoil. The hulls are so light that they rarely come close to being balanced after you slap 4 strokes on. The foil helps the ride in chop by holding the nose down and helps get on step easier. I wish more builders would address this and move fuel tanks and batteries forward.

I've got to build a hold-down for the dual batteries under the bow stairs

move 100 lbs of batteries forward