I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

[rs2k]

I have a really big and heavy foot tri-hull that needs trim tabs. It is only 17 feet long, but it weighs 3000 lbs, has an 8 foot beam, and a close to 3 foot freeboard.

It runs great at 35 MPH. Very flat and its a breeze to turn. At 18 - 20 MPH it runs really nose high and tends to want to fall off of the plane very easily. I'm 6'2", but even I have to stand up to see over the bow when cruising at 20 MPH.

My stringer outdrive does not have trim capabilities, but I can adjust the motor mounts a bit to set the angle of the outdrive. I like the cost and ease of use of the automatic trim tabs I've seen, but I'm a bit skeptical.

 

[jdlough]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

I can't quite imagine this boat. 17' X 8', high freeboard Trihull, 3000lbs?

Pictures would REALLY help.

Jim

 

[rs2k]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

She's a big heavy beast. I'm sorry for the black outs, but the previous owners might not like themselves on the net.

 

[Jdeagro]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

The overall weight is not the issue as much as balancing that weight. Since you did not give us the motor type and HP info I can not make a full reccomendation, but my first choice would be the ST1290-60 which provides a bit more tab size. The next would be the SX9510-60.

 

[rs2k]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

It has a chevy small block and the boat is rated for up to 260 HP. Its old tired 305 probably is only putting out about 160 right now, but I do plan on putting a new motor to get the entire 260 out of it.

 

[rs2k]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

What speed range do those tabs work at? I don't need any trim after 32 MPH.

 

[rs2k]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

I'm sorry, I made an error on the boat length. It is actually an 18 footer. My other tri-hull is a 17 footer.

 

[Lliam]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

I have a 17 foot OUT BOARD center console aluminum boat.
I have a built in fuel tank
How do I find the manufacturer for this boat?

 

[Chevysolid]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

So far, I can tell you that the installation of the Smart tab sx's are a breeze, 20 minutes....

As for a field test on a 19.5 ft, 3000 lb boat I should be able to let you know early next week....

Read the other feedback, it has been positive for all I can tell, that is what I went with...

Other thing.... that old of a boat, you probably do not want to spend a fortune, 100 bucks was pretty reasonable for what is offered, can also maybe try a four blade prop too?

 

[tashasdaddy]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

you can beat these for that boat, the most bang for the bucks. even with the new motor.

http://www.iboats.com/Factory_Blemi...z.54646--**********.812045333--view_id.486634

 

[nlain]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

What speed range do those tabs work at? I don't need any trim after 32 MPH.

The Smart Tabs are deployed at stop or low speed for stern lift to help get on plane, once on plane water pressure raises the tabs which helps keep the boat balanced with more hull out of the water, also helps to stay on plane at slower speeds among other things that are good.

 

[Chevysolid]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

Finally got out on the water with the new smart tabs,
BIG difference on bow rise, I did not even have to get off the seat to see over the bow during acceleration... As for better acceleration and lower plane speed, still inconclusive.... seemed to stay up on plane a bit better at around 20 mph or so... But it was nice, I did not have to give it over 3500 rpms to get up on plane... Normally would have to mash it get up on plane and then back it off.... now Just put it at 3000 or 3500 and it goes right along and up onto plane...

 

[Jdeagro]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

Chevy; Do you know the WOT speed before you installed the tabs? Are you now trimming the motor out to get the best prop bite? If the boat does not exceed the WOT speed before tabs, reduce the pressure - it will increase the speed.

Can you immagine the fuel savings now that you do not need to use full throttle to get up?

 

[southtexas]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

I've got a 20' flatbottom with 8' beam (and only a 115hp outboard), weighing close to 3000lbs fully loaded. I have the SX 9510-60 on mine and they have made a world of difference. They eliminated bowrise; I picked up 20% on top-end; handles much better now. They are VERY easy to install; a buddy and I did it at dock--first one took about 30 min, second one took about 10 minutes. Can't say enough about how great these perform.

 

[Chevysolid]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

J.
I only had the boat out twice and was running (speedo showed) 48-50 mph... and it doesn't seem to have changed much.... I bring my trim up 1/4 from down all the way and I start to (either cavitate or porpoise?) revs up with no real gain on speed....
Still messing with it may try moving the shock up one step to get less pressure... I also installed a four blade prop...

 

[Jdeagro]

Re: I need trim tabs for my heavy 17 foot trihull, what kind whould I get?

Less pressure would be down not up. Example: on the SX series you would go from hole 3 to hole 2, not hole 4. Do not confuse this adjustment with changing the plate deployment angle, this adjsutment only changes the leverage point and therefore the lift pressure. let us know!