How do I know that I have already achieved the ideal Smart Tabs settings ?

[hdradaza]

I have an 18 footer tri hull with extreme porpoising problem and planing.

I installed the smarttabs sx and placed it in the middle hole as suggested. This controlled the porpoising (but not eliminated it) and yes I was able to plane quicker.

The next time out, my mechanic suggested adjusting the hole since there was still some porpoising. So we moved it to the hole farthest away from the transom to increase the pressure.

This according to them did minimize the porpoising further.

1) How do I know what the ideal setting is for the boat?
2) Does putting it on the furthest setting (away from transom) put more drag on the boat ? I had 8 on the boat and it seemed we were almost dragging along at 3500 rpm...

 

[tashasdaddy]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

8 people on a boat is a lot of load. don't remember what boat and motor you have.

 

[hdradaza]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

18 footer tri hull with 150 hp.

Link to boat here - http://forums.iboats.com/showthread.php?t=230922

Oh and ya.. I had a full tank of gas and full load on the cooler

 

[nlain]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

If all of the 8 people are adults and full figured you probably are overloaded, so if you feel you have too much pressure on the tabs back off the tab pressure and back off the motor trim a little. With your load you have a balance problem and you will have to play with the settings to balance out the boat, when that happens you will be able to tell the difference. You should still plane faster, no porpoise, run a little faster, have a better ride and most of the other things advertised. I would also recommend that you call John at Nauticus and talk to him, explain it all to him and he can advise the best thing to do.

 

[Cruiserman]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

Just thought I would throw in my input on smart tabs.. One of my crafts is a Searay 180 Bowrider 1988 with a 4.3 and alpha one.. When I first got the boat I noticed a wander at slow speed. It was suggested to me to try some sort of trim tab fully deployed to help the steer-ability of the boat at slow speed. I decided that the craft was too crappy to invest in fully functioning hydraulic tabs.. so I started to explore smart tabs. I was skeptical and asked a lot of questions. I had invested a bunch of money in re-power with a 205 4.3 as well as general rebuild of the interior of the craft. We used it for tubing and skiing . The top speed skirted just under 50 in calm wake. The recommended tab was of certain size and employed #80 lb piston thingys. This produced great low speed steer characteristics but the top end was wandering, walking and rolling and felt very unsafe. It was further suggested that for a searay 180 that I should try #60 piston thingys (suggested by the smart tab people) .. which I did.. and behold... the chine walking ended.. I was up on plane at much lower speeds and it felt like I had a real performer going on. I mention all of this to anyone who is thinking about smart tabs on a 180 .. go with the 60s.. it is absolutely tuned for that boat. Enjoy .. ps.. in a "tuned" situation the tabs increase the top end as they allow more of the boat to be out of the water. I was easily doing 50 now and not white-knuckling for minutes as before. I cannot speek to different years or models of searays.. I am referring to the searay Seville class 180 of the late 80s with a 4.3 v6 and alpha 1 in calm wake.. and with no planning wing thingys on the outdrive...

 

[nlain]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

Well written reply Cruiserman, the 60lb actuators are actually for the IO configuration, the 80lb are for the OB configuration, when I purchased mine I had the 80lb actuators and could not get the bow up, called John told him what I had and before I finished he said I nedded the 60lb, which he sent, I would not be without now. They are great.

 

[tashasdaddy]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

yes that was the boat i was thinking of, very nice job. but i think you have a tendency to overload your boat. especially if some of the are full figured.

 

[hdradaza]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

ya they are full figured. heheheh

Ok, so when doing the test ride and calibrating the smarttabs, what should be my boatload ? Should it be just me ? Or should it be my usual load ( 5-7 pax ?) ?

 

[Jdeagro]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

hdradaza;

You must have our new SX series, and if you look at the plate you will see the adjustment holes are numbered 1 through 5. One being the least pressure and 5 being the most. Moving the actuator from 3 to 5 may have been too much. What you are trying to accomplish is boat balance. Too much pressure will drive the bow down and cause bow steering, listing, leaning in turns, and a loss of top speed. Too little pressure may not eliminate the porpoising. Also, you should use your tilt and trim. Down when you are at slow speeds and up or out to vertical when you are at cruising speeds.

As for testing, it sounds as though you are expecting the boat to perform the same regardless of the weight and load. That is not likely! Eight people in the boat at one time is a bit much for an 18 ft boat. Test the boat with an average load. Run it without the tabs functioning (tie them up so that they are not deployed - no need to take then off) to get a base line. Then activate them and check the results. If the boat is not faster at the top end then you have too much pressure. If the porpoising has not been eliminated then you have too little pressure.

 

[tashasdaddy]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

you really need to reduce the number of people you take in the boat. some passengers, even though the don't take the space of two, you have to count as two. boats do not only and a per person load limit, they have a total weight limit. the weight limit comes first. two 300lb passengers or 4 150lb passengers.

 

[Cruiserman]

Re: How do I know that I have already achieved the ideal Smart Tabs settings ?

The placard on my Searay 180 reads 5 persons or 960 total lbs..... The hole settings I found to be a subtle fine tune.. they were ineffective to retune the smart tabs if grossly incorrect. The Idea behind the system is that they are dynamically moving up or down as the boat is traveling.. The load and weight distribution in a small craft with ST still needs to be evened out by seating arrangement as per the call of the captain. To have a system that allows you to dynamically tune your load at the helm would need to be fixed such as bennets. Smart tabs are to be used to plane at slower speeds, achieve higher top end and to reduce steering wander at headway.. Its obvious that changing the smarttab settings everytime you would need to would be silly...They are also fully deployed in reverse.. so go slow.. and there were times in higher seas that I gerryrigged a way to keep them up as to allow the bow to raise and my trim to respond appropriately. They are great for smooth water, very light chop, watersports, and the like. But will not take you in all situations you may encounter, but face it, a small boat is a small boat...