Upgrading Tabs

[BradV]

After talking to Lenco several times on the phone and speaking with their engineers about what would work best for my boat and showing pictures I am going to upgrade the tabs. I currently have 16" long by 12" wide tabs on the boat now. To go much bigger to something like 24 long xy 14 wide I would have to go to a dual actuator with a backing plate. Which doesnt work because of the scupper location. Not to mention its like a $2800 upgrade. So I picked up the new tabs yesterday and will try to get them on today. They are 14wide x 18 long. These are the only size bigger that i can use that works with the actuator and wiring that is currently on the boat. Here is what I have currently on the boat and I will take some pics as i go on. I didnt think that they would be that much different but after putting them next to each other the new ones seem pretty substantial plus they are a larger guage of stainless so i am hoping that i wont get as much flex out of them.

 

[Bryan 2530]

FWIW, you can buy a complete Bennett 12 x 24 system for around $600.00. No need for "dual actuators". You can forget Lencos.

IMO, yer need at least 12 x 24: if room, 12 x 30.

Why are yer tabs mounted 1/2" above hull bottom ?

Can't do that with twins.

Brad, are you going to have to move the actuator??

 

[grouperjim]

Why are yer tabs mounted 1/2" above hull bottom ?

Standard Parker install.

Lenco tabs have a piano hinge and cannot be mounted flush with the hull bottom. if mounted flush, a large a amount of spray will shoot thru the hinge. Lenco recommends raising the tab 3/8" to eliminate the spray issue.

i prefer Bennet tabs because the hinge is solid with no welds and can be mounted flush with the hull bottom. i prefer the Lenco electric actuators which work just fine with the Bennet blades.......best of both worlds.

 

[BradV]

yeah 14" wide is the widest that i can do with twin motors. I actually spent some time on the phone with Bennett and they flat out told me that they couldnt do anything for me. The biggest they had was something like 12 x 12 or maybe 14. Either way it wasnt as big as my current tabs. Lenco does recommend keeping the tab 3/8" above the hull bottom. I didnt have a preference really with who i went with just wanted something that would work. I was able to leave the actuators where they were just had to drill 10 new holes per side. The original holes didnt work except for the center hole. I ended up keeping it centered and going 1" both ways. This was based on the recomendation from Lenco. I was leaning more towards putting the actuator off center by 1" but they said this was better.

 

[BradV]

I ended up calling and sending pictures to the engineers and testers at Lenco and the position and ending locations of the tabs is what they told me to do. i will test it tomorrow and see how it works out. I sealed up the old holes with 5200 since youll never see them anyways. Pretty simple project. I also took the zincs off the old tabs.

 

[BradV]

Some more

 

[grouperjim]

Brad.......i know you have heard it before but all you need are a set of Permatrims and you ass heavy sensation is cured. You'll also feel that your existing tabs are adequate as well.

a member on THT "The Pig" put them on a new Parker 25 dv and a 28 dv, both with twins on a bracket and he swears by them. he runs the boats as passenger ferries in the Bahamas

http://www.thehulltruth.com/boating-for ... rim-2.html

if for whatever reason you don't like them, the holes in the a/v plate can easily be filled with MarineTex and painted with some motor paint. If you buy from Andy at Sim, he will even take them back if not satisfied.

 

[MaxOut]

I agree with Grouperjim the Permatrims or similar will do more than the small gain in tabs without robbing your fuel economy. I know its a little late to turn back on the tabs but if you are still not satisfied I would go with the Permatrims.

 

[BradV]

I actually tried out a product similar to the permatrim and was not happy with the performance and ride that it had on the boat. It definately raised the stern of the boat but made it so the bow couldnt come up which wouldnt be good for those long runs in a following sea. Also, fuel economy and top end were worse. The boat runs fine most of the time the only time it becomes an issue is when im really loaded up for bahama runs. I truthfully dont think that the plate would be able to handle the torque. I have spoken with Andy a few times about the permatrims. Just feel like having the option of deploying tabs is better than something fixed because the boat gets weight distriubuted differently depending on diving, bahamas, return trip from bahamas. I am thinking that these tabs should make enough of the difference that i am looking for. I am definately leary on using permatrims on twin engines because thats a lot of extra surface in the water.

 

[BradV]

http://www.thehulltruth.com/permatrim-m ... bolts.html

 

[grouperjim]

you're right with twins, that is a lot of extra planing surface so the effect is even greater. more like the handling of a hull with a notched transom. the boat rides longer as the pitch axis is moved aft.

to negate the effect of the Permas you simply trim the engine up, no different than a trim tab. the Perma is more like a tab than a hydrofoil because the planing surface area is aft and not out to the sides like a foil.

the SS bolts that hold the Perma to the a/v plate can break if over tightened as with SS bolts anywhere. SS is a soft metal. the bolt on the Perma that is under the most stress in the aft starboard bolt. i did over tighten this bolt and it snapped. no biggie, replaced in less than 5 minutes.....good to go. you're not going to hurt the a/v plate regardless.......that's never happened, twins or otherwise.

 

[BradV]

taking it out today to go fishing. probably wont know if it will do that much different until we go to the bahamas again. but i will report back either way.

 

[Bryan 2530]

Brad, how much were the plates??

 

[BradV]

200 per plate. i actually got to use them today more than i thought. Pretty happy with the difference. I was able to run the motors at 3300 rpm at around 19 mph. Granted i was with my uncle and had about 70 gallons of fuel. The waves were pretty sporty. We had a nice north wind stacking up against the north current. We actually had a wave that looked pretty big end up cresting and crashing over the transom which was interesting. Anyways I think it is going to do what i want it to at this point. Ill report back if it doesnt.

On another note we ended up with 5 yellowtail snappers, 1 mutton snapper, and a little shark.

 

[Bryan 2530]

Bumping this up.

I don't think Brad is on here anymore since he sold his 2530, but I think the new owner is.

This is an upgrade I want to do, any one have any input???

Best place to buy replacement blades??

 

[SCL]

I would check with west marine. I replaced my tabs with 12x18s last summer, payed about 300 for the pair. They where able to order direct from Lenco. April is right around the corner

 

[DaleH]

OMG :shock: ... guys, the LAST thing you want to do with a trim tab is add depth OFF the hull. Wider is better ... repeat ... wider is better.

Now will those tabs work? Yes, but they will KILL your fuel economy BIG time! Std Lenco tabs and a Permatrim or other foil would be a much better option IMHO.

 

[WAJSKI]

Has anyone tried the SE sport hydrofoil?

 

[Bryan 2530]

Problem is, with twins you can't go wider without cavitation, so that is the best I can possibly do on my transom.

Go fast boats do it all the time with longer tabs, problem is as you go longer you have to step up to dual actuators.

 

[pmeggers]

The regulator has longer thiner ones. No issues.