Use of trim tabs to get on plane

[muskyfins]

My Rinker 270 has a bit of a tough time climbing out of the hole. I have tried to "tab down" to reduce the time to plane but it didn't seem to change it. There is a label on the tab switch that reads not to use the tabs for anything other than side to side control. But I have heard several people mention to use tabs to improve planing. What is the recommended protocol? What do you other folks do? Kinda just wondering....:watermelon:

 

[Scott Danforth]

Depends...... I use my tabs down a bit to allow a slower speed while still on plane. However the tabs don't seem to help getting back on plane.

Drive in and throttle down for a quick blip back to planning, then I raise the drive a bit and throttle down to desired speed

The 27' is a large boat for an sbc, especially climbing the hole

 

[tpenfield]

Yea, tabs do as much to slow you down as they provide lift for the stern. You are better off using the outdrive trim and sending some 'weight' forward than trying to use the tabs . . .

Also you need a bbc or sbc twins in that boat(sorry to say)

 

[muskyfins]

Yeah, a big block would have been great. Twins would have been better. I would have settled for twin 4.3's.

But in the end, I traded from my 1994 to my 2000 for even money. Couldn't pass it up. But the 94 with a SBC and a bravo2, seemed to get up better??:noidea:

Once she's on plane, it's fine. (actually there is a really weird issue once on plane but I'll start a new thread when I get a chance)

Tops out at 38/39 GPS speed. Cruise 33 ish at 3,900. I can live with that.

 

[Blind Date]

Yea, tabs do as much to slow you down as they provide lift for the stern. You are better off using the outdrive trim and sending some 'weight' forward than trying to use the tabs . . .

+1

Have you looked into pitching down. That's a lot of boat to move with a SB V8.

 

[Tabman]

Trim Tabs can do an excellent job in getting a boat on plane faster and with far less bow rise. Sort of like flaps on an aircraft. But they must be large enough, and many boat builders install Tabs that are too small (in our opinion).

Larger Trim Tabs actually create less drag in relationship to the lift they generate since they need to be deflected less than smaller ones to make the same or more lift.

We spend lots of our time helping folks install larger Trim Tabs than the ones their boats came with, with excellent results.

Tom
Bennett Marine

 

[Scott Danforth]

Tom brings up a good point.

any idea on the maximum length trim tab that would be recommended with a single actuator?

 

[Tabman]

The largest tabs we make with single actuators are 42" x 12" and 54" x 9".

Tom
Bennett Marine

 

[frantically relaxing]

I have to disagree on the tabs not helping out of the hole because they slow you down-- I mean, you're STOPPED, when you take off, can't hurt much there! -- and the drag is insignificant if your boat needs the help.. Half of my boating life has been spent on lakes above 6500', and Lake Powell is the lowest elevation I've ever boated on (3600') My Sea Ray has tabs and has ALWAYS got up on plane nearly instantly with the tabs down compared to when they're up. Our old Sun Runner 252 wouldn't even get on plane at Flaming Gorge (6400') without the trim tabs down. Needed a prop change at Strawberry (7600') in addition to the tabs. With those boats it was SOP for me to put the tabs down whenever I slowed down so they'd be ready. When taking off, as soon as the boat would break, I'd put the tabs full up, trim the drive, then trim the list. The Sea Ray has a sweet spot with the drive up so far and the tabs down just right where it do 32+mph at 2800 rpm with 19" prop, You can feel when it happens, and it won't happen unless the tabs are down.

Granted, some boats don't need them to get on plane. Consider yourself lucky if you have one! Our Regal doesn't need them, which really surprised me, I really didn't notice a difference. It planes in 7 seconds with or without them. Sure do need them afterwards!

A blanket statement that tabs down won't help a boat plane out just isn't accurate. It really depends on the boat...

 

[Mischief Managed]

I pretty much always use tabs for getting on plane, solely to keep the bow from rising. My 25' boat has a big block and a Bravo 3, so it will plane out easily without them, even with a full load of people, but it has a stepped-hull and 24 degrees of deadrise, so there's quite a bit of bow rise without tabs, and it annoys me. With the tabs down, the boat stays level as it accelerates, like a ski boat.

My Bennett tabs are factory-installed and probably a little small, but they work great and I LOVE them. My acceleration routine: 1. Tabs down all the way, trim down all the way. 2. Throttle to 3/4 or so. 3. Immediately start trimming the drive up to open the exhaust and let the engine breathe (you can feel it gain power) while accelerating. 4. The boat gets to about 28 to 30 MPH quickly. 5. Bring the tabs all the way up. 6. Back off the throttle to 1/2 or so for my desired cruising speed. This process takes maybe 20 seconds. After that is all done, I then use the tabs to adjust listing or smooth the ride, as needed.

 

[shaw520]

1990 SR 280 with twin 5.0's,.. (8500 pnd and 31.6 OAL) trim tabs DEFINITELY help me get on plane. The protocol that works best for me;
outdrives trimmed all the way down
Trim tabs all the down
Slowly power up,... once on plane tabs gradually up for ease and comfort of ride,... stern drives up slightly to reduce torque and drag,.. boat becomes happy at around 3100 -3200 RPMs (24-27mph)