Smart tabs on trihaul

[shawn.54]

I have 1977 starcraft capri 15 and was wondering if anyone has smart tabs on a tri?

 

[smokeonthewater]

Re: Smart tabs on trihaul

It's a triHULL..... Smart tabs work equally as well on a tri as they do any other.... Nauticus has great customer support.... check out their website and give em a call... they are known for telling it exactly as it is and not just trying to bs you into buying their product.

 

[eavega]

Re: Smart tabs on trihaul

I had smart tabs on my 15' Yar-Craft tri-hull (circa 1976). They definitely helped the hull plane a lot faster, especially when I was underpowered with a 50 HP. I later got a 70 HP for it, so the trim tabs were not as vital at that point. It took some jiggering to get the boat trimmed out correctly (no PTT), but once I got the motor height and angle, as well as the right setting on the smart tab, that boat would positively jump out of the water.

I had removed a "whale tail" that a previous owner had put on it to try and get the boat to plane with the 50. I found that the trim tabs worked better than the whale tale in getting the boat to plane quickly, plus it didn't affect turning the way the whale tail did.

Rgds

 

[eavega]

Re: Smart tabs on trihaul

I had smart tabs on my 15' Yar-Craft tri-hull (circa 1976). They definitely helped the hull plane a lot faster, especially when I was underpowered with a 50 HP. I later got a 70 HP for it, so the trim tabs were not as vital at that point. It took some jiggering to get the boat trimmed out correctly (no PTT), but once I got the motor height and angle, as well as the right setting on the smart tab, that boat would positively jump out of the water.

I had removed a "whale tail" that a previous owner had put on it to try and get the boat to plane with the 50. I found that the trim tabs worked better than the whale tale in getting the boat to plane quickly, plus it didn't affect turning the way the whale tail did.

Rgds

 

[eavega]

Re: Smart tabs on trihaul

I had smart tabs on my 15' Yar-Craft tri-hull (circa 1976). They definitely helped the hull plane a lot faster, especially when I was underpowered with a 50 HP. I later got a 70 HP for it, so the trim tabs were not as vital at that point. It took some jiggering to get the boat trimmed out correctly (no PTT), but once I got the motor height and angle, as well as the right setting on the smart tab, that boat would positively jump out of the water.

I had removed a "whale tail" that a previous owner had put on it to try and get the boat to plane with the 50. I found that the trim tabs worked better than the whale tale in getting the boat to plane quickly, plus it didn't affect turning the way the whale tail did.

Rgds

 

[greenbush future]

Re: Smart tabs on trihaul

why do you think you need them?
what power are you running?

Might just be water logged, what's the floor transom, foam and the rest look like?
Could just be underpowered, but I would be concerned why the are even needed. They will help a bunch, the are pricey, IMO.

 

[shawn.54]

Re: Smart tabs on trihaul

75 evinrude it does fine untill i ski 300 plus just looking for little quicker hole shot.

 

[Chris1956]

Re: Smart tabs on trihaul

no boat will perform well with a 75HP motor and a 300# skiier. You need more power. tabs should help some.

 

[Jdeagro]

Re: Smart tabs on trihaul

Hi Greenbush;

I agree that you should not use trim tabs to correct an unknown problem such as water saturation. However, I cringe when anyone mentions that the boat may be "underpowered". This is often not true and indicates that the best way to make the boat perform correctly is to add HP. Obviously a 10 HP motor on an 18' bowrider is underpowered for towing skiers, but most boats simply don't use the available power correctly.

Keep this in mind when considering HP; How much of the HP is used to "climb"up hill to get on plain vs the necessary HP to cruise at 1/2 to 3/4 throttle (25 to 30 MPH)? Without trim tabs nearly all of the available HP is used to get out of the "hole". Why not simply eliminate the "Hole". Why try to accelerate UP Hill? Trim Tabs (when deployed) provide the extra stern lift to compensate for the extra stern weight. The typical bow rise during acceleration is 15 to 17 degrees, and that is quite a hill. What if the bow rise was only 5 or 6 degrees? How much less HP would be required to get on plain? Keep in mind that the HP rating is measured near the top of the RPM range (ie: 5000 RPMs). At 2000 to 2500 RPMs during acceleration the engine is producing less than 1/2 of the rated HP.

Let's look at what you get for the extra dollars when you step up from a 100 HP to a 135 HP motor for a typical 18' V bottom bowrider.

The 100HP motor will push the boat to about 36 MPH at WOT. The 135 HP motor will push the boat to about 39 MPH with the same load ( net gain of 3 MPH at WOT.)

The 100 HP motor produces 50 HP at 2500 RPMs while the 135 HP motor produces 67 HP which is a net gain of 17 HP while weighing another 30 to 50 Lbs.

Which boat will get on plain easier and quicker if the bow rise is reduced from 15 degrees down to 5 or 6 degrees? Eliminate the Hill.

Top speed is also likely to increase with the smaller motor because the trim can be adjusted without concern for porpoising, and the running surface is extended (trim tabs retracted).

Am I saying that the 100 HP powered boat with trim tabs) will accelerate to plain faster than the same boat with a 135 HP? Absolutely!

However, the 135 HP numbers on the cowling are more impressive. Buy some new decals By the way, "yes" the 135 HP will perform even better with trim tabs.

 

[southkogs]

Re: Smart tabs on trihaul

I used to play with a neighbor at our cottage who had a mid-70's Starcraft with a 70(ish) HP O/B on it. Our boat was a 15' tri-hull with a 65HP. Both boats would pull one skier (around 170#) out pretty easily. Two skiers would have to work a little to get up (probably in that 300+ zone), and we could get 3 up if they were willing to fight it out.

While tabs will gain you "something," bear in mind that you're asking a smaller boat to work like a more powerful boat.

 

[ricohman]

Re: Smart tabs on trihaul

I had a 79' Capri 15 with an 80 merc.
I never wanted or found I needed tabs.

 

[shawn.54]

Re: Smart tabs on trihaul

I relize that i need more hp got this boat cheap was out of boating 12-15 years had not skied in that time was on topthe water 3rd try 42 years old dont think rig did a bad job that was wife two boys 12 gallon fuel in boat. just want little more help out of hole. she does stand up on takeoff.

 

[smokeonthewater]

Re: Smart tabs on trihaul

Nobody who gets smart tabs ever regrets it... If you do I'm pretty sure they'll take em back.

 

[Stachi]

Re: Smart tabs on trihaul

It's a triHULL..... Smart tabs work equally as well on a tri as they do any other.... Nauticus has great customer support.... check out their website and give em a call... they are known for telling it exactly as it is and not just trying to bs you into buying their product.

I once towed a trihaul with a U-Hull rental truck.... lol

 

[shawn.54]

Re: Smart tabs on trihaul

did you take that to a church hall?

 

[jestor68]

Re: Smart tabs on trihaul

Have you considered a prop with less pitch for heavy duty pulling. Tabs won't produce any more pulling power. A lower pitch prop will.

Lots of folks have a "ski prop" that is 2" less pitch than their general purpose prop.

 

[Jdeagro]

Re: Smart tabs on trihaul

Jestor68;

Have you ever tried trim tabs? You are correct that the tabs will not create more power or torque, but they do re-direct the power. Even with a prop change the "Hill" still exists. Time to plane with trim tabs will be better than time to plane without them and with a lower pitch prop. We have done numerous tests over the past 13 years. Not only that but the fuel economy will improve. Fuel economy with a lower pitch pro is like driving around in 2nd gear all day.

There has been so much emphasis on prop changes over the years that it has become the "common" answer to all performance issues.
If you are going out for a day of skiing and wish to change the prop for that purpose just remember to change it back later, but if you want the best combo, use trim tabs and change the prop. Be careful not to over rev the engine.

 

[greenbush future]

Re: Smart tabs on trihaul

Hi Greenbush;

I agree that you should not use trim tabs to correct an unknown problem such as water saturation. However, I cringe when anyone mentions that the boat may be "underpowered". This is often not true and indicates that the best way to make the boat perform correctly is to add HP. Obviously a 10 HP motor on an 18' bowrider is underpowered for towing skiers, but most boats simply don't use the available power correctly.

Keep this in mind when considering HP; How much of the HP is used to "climb"up hill to get on plain vs the necessary HP to cruise at 1/2 to 3/4 throttle (25 to 30 MPH)? Without trim tabs nearly all of the available HP is used to get out of the "hole". Why not simply eliminate the "Hole". Why try to accelerate UP Hill? Trim Tabs (when deployed) provide the extra stern lift to compensate for the extra stern weight. The typical bow rise during acceleration is 15 to 17 degrees, and that is quite a hill. What if the bow rise was only 5 or 6 degrees? How much less HP would be required to get on plain? Keep in mind that the HP rating is measured near the top of the RPM range (ie: 5000 RPMs). At 2000 to 2500 RPMs during acceleration the engine is producing less than 1/2 of the rated HP.

Let's look at what you get for the extra dollars when you step up from a 100 HP to a 135 HP motor for a typical 18' V bottom bowrider.

The 100HP motor will push the boat to about 36 MPH at WOT. The 135 HP motor will push the boat to about 39 MPH with the same load ( net gain of 3 MPH at WOT.)

The 100 HP motor produces 50 HP at 2500 RPMs while the 135 HP motor produces 67 HP which is a net gain of 17 HP while weighing another 30 to 50 Lbs.

Which boat will get on plain easier and quicker if the bow rise is reduced from 15 degrees down to 5 or 6 degrees? Eliminate the Hill.

Top speed is also likely to increase with the smaller motor because the trim can be adjusted without concern for porpoising, and the running surface is extended (trim tabs retracted).

Am I saying that the 100 HP powered boat with trim tabs) will accelerate to plain faster than the same boat with a 135 HP? Absolutely!

However, the 135 HP numbers on the cowling are more impressive. Buy some new decals By the way, "yes" the 135 HP will perform even better with trim tabs.

Great write up and explanation, not much I could add to your view.
Many times boats have other reasons for not performing as well as desired. That was my focus with the questions I asked. Then to learn that the skier is at 300#, explains whey the problem exist's.
The other reason some older boats don't get on plane well is soggy foam under the floors, rotted floors, tired engines, under powered engines and the rest. Trim tabs could work with some of the problems I mentioned, but that would still mean the boat has some serious issues, that if left unchecked, could cause an accident.

 

[shrew]

Re: Smart tabs on trihaul

Nothing like a smart tab vender trying to convince you that his product is the solution to your problem. Next the Prop vendor will be on to tell us why his recommended prop change is the best solution. Then the foil guy, to convince us why his foil is the best solution.

 

[crabby captain john]

Re: Smart tabs on trihaul

Nothing like a smart tab vender trying to convince you that his product is the solution to your problem. Next the Prop vendor will be on to tell us why his recommended prop change is the best solution. Then the foil guy, to convince us why his foil is the best solution.

There are 2 tab vendors here. Both provide info with no pressure. Wish I had tried Smart Tabs in the past. After several boats with Bennets the last one was not as exciting so when the current boat arrived it had Lenco tabs installed. No complaints with them and may even like them just a tad better.