Tilt Trim Position while Running

[phwrd]

Hey ya'll,

I have not found any good advise on what is the best position for my trim, motor angle, at what speed ?

Down, Up or inbetween ? Best gas consumption, best overall speed ? Are there any threads out there that i missed ?


Thanks

 

[Jamie Z]

Re: Tilt Trim Position while Running

I'm new to this, but one thing I've noticed is that without changing engine RPM, changing the tilt can add or subtract a few tenths of a knot up or down. Clearly, the trim has an effect on efficiency, but I suspect it varies depending on conditions.

Jamie

 

[Pez Vela]

Re: Tilt Trim Position while Running

TMI?

http://books.google.com/books?id=my...v=onepage&q=adjusting boat trim angle&f=false

 

[jaxnjil]

Re: Tilt Trim Position while Running

i like to trim what ever rpm i want to run.
i get the rpm and then trim to the most gps mph i can get at that rpm.
i had a fuel flow meter for awhile and that is also the most economical setting as a general rule.
on still glass you can trim bow up higher than if the lake is running. then you will want to drop the bow and cut the waves for a better ride. heading will always make a difference. in to the wind and weather away from or quartering all change the way you trim at the time.

as a side note we had an alpha drive and bumping the trim up or down a little bit could make quite a difference at times. you could piddle with the trim and get to a sweet spot. now we run a b3 and it it isnt near as fussy about where the trim is set.
it must grab enough water so that its effective in a broader range of trim positions. it seems like it dosnt want as much as the old alpha used to like.

 

[Jeep Man]

Re: Tilt Trim Position while Running

Trim will vary, depending on the angle of the hull. Ideally the prop will be 90 degrees to the surface. As the angle changes due to speed and load, so should your trim.

 

[tashasdaddy]

Re: Tilt Trim Position while Running

rule of thumb. getting out of the hole, trim all the way down, when bow drops start to trim out, every boat is different, find the happy spot. it will differ in conditions, weight, and placement of the weight.

 

[JoLin]

Re: Tilt Trim Position while Running

rule of thumb. getting out of the hole, trim all the way down, when bow drops start to trim out, every boat is different, find the happy spot. it will differ in conditions, weight, and placement of the weight.

+1

It does vary from boat to boat. On my old Pro-Line outboard, it was pretty simple- in smooth water I'd trim out until I felt a hint of porpoising, then trim down a touch and I was set. My GPS confirmed that this was a good way to do it. In rough water I'd trim out until the ride got uncomfortable (pounding), then trim in to force the bow to cut the waves.

My C-C rides differently, and I trim first by GPS (up) to best speed, then generally start trimming down a bump at a time until I get best ride for the conditions. I know, it sounds like the same thing, but it seems to take a little more finagling on this boat, but with experience it gets easier. Between the outdrive trim and my Bennett trim tabs, I do feel like I spend an awful lot of time bumping buttons.

 

[LIQUID PROZAC]

Re: Tilt Trim Position while Running

ditto tashasdaddy--trim down to take off and when on plane trim up until starts to porpoise slightly and trim down until gone=my sweet spot

 

[180Fisherman]

Re: Tilt Trim Position while Running

Be the boat, Danny. Be the boat.

 

[Subliminal]

Re: Tilt Trim Position while Running

I haven't even gotten my boat yet, but I know when I drive my neighbors boat with the outboard, you start trimmed all the way down and you trim up until the speed stops going up and then futz with it a little to get the best speed out of the RPM you want to run.

 

[Home Cookin']

Re: Tilt Trim Position while Running

There are so many variables involved; hull design is one. Often your purpose in trimming is to minimize spray entering the boat. You can run a flat-bottomed boat over shallow water to help get up on a plane from the water pressure. You might trim differently heading into the wind to use the lift. Every boat, and every boating day, is different, at least where and how I boat.
One tell-tale of good trim is the wake--you want the minimum, which shows that the hull is travelling with the least resistance and therefore more efficiently. You don't want your bow plowing or your stern dragging--unless you are adjusting for waves, wind or spray.