Optimal trim tab settings for flat sees

J

Jeff_e_d

New member
I seem to get an extra mph or two on flat sees when the trim tabs are all the way up, but I'm not totally sure on that one. Seems to be less drag. Any other thoughts....?
 
That makes perfect sense to me too. Of course if the boat is loaded uneven it is going to run either heavy to port or starboard and that needs to be corrected with the tabs, as that is what they are designed for if memory serves me.

Tabs are a dynamic tool, to be used where needed and kept up when not needed.

If the boat is out of balance due to load, correct it using the tabs or by moving gear aft or forward , or both if needed.

The less drag the better your gas milage will be.
 
This summer I have been experimenting with different props, trim tab, and motor trim positions. While I am not done yet, with a Propulse prop on my 90 ETEC, I found I got the best fuel economy at less than WOT on flat seas with the trim tabs in down position (about 5 lights on the Bennett indicator) with up trim on the motor. In other words, the boat wanted its bow down some (or stern up) so it presented the least angle of attack to the water flow. The motor was most efficient when the propeller is parallel to the water flow. The lesson on that configuration was set the trim on the boat with the trim tabs and not the motor.

I wish I had a trim indicator on the motor in order to duplicate certain trim conditions. After watching the fuel flow meter it doesn't take much change in motor trim to send fuel economy the wrong way.

Of course the biggest factor in fuel economy is passengers who won't stay in their seat and water that isn't perfectly flat. All the work on getting the best trim goes out the window.
 
Tom-

Very ionteresting information and observations!

"I wish I had a trim indicator on the motor in order to duplicate certain trim conditions."

There isn't a motor trim indictor integrated in the etech controls and gagues?

Joe.
 
Joe,

I wish. I didn't even see it as an option. I am about ready to calibrate a mark on the motor housing with a mark on my work table I can see from the helm. That way I know where I am in relation to a given point. Crude but it would give a reference.
 
Tom-

I've got a little 10 bar vertical trim indicator on my Yamaha main gauge console and kind of figured is was pretty standard in the industry.

Joe.
 
For 23 years I have been trying to balance out my boat by keeping my 300 lb. butt on one side, my friends 280 lb but on the other side, my wifes tiny(for PR purposes)butt in the middle, keeping my fuel tanks even and putting our halibut evenly on each side.
Has anyone installed and used a set of trim tabs on the old true flat bottom C-Dory with good results.??? I have a complete set-up but did not install it as I don't want anymore do-dads on my boat for fishing line to catch on than necessary. But I am getting tired of the leaning one way or the other.
Thanks for any info...........Jack
 
Jack-

Your question- "Has anyone installed and used a set of trim tabs on the old true flat bottom C-Dory with good results.???"

Red Fox has done so, and loves 'em! In fact, he expanded them out until they're 9' x 18', or so with double activation cylinders.

You might try to search his site or this one to see if you can find reference to them.

Joe.
 
Back
Top