Running attitude, speed - 2002 410DA 3126 CATS

[dyerdan]

So we dropped in yesterday, and all is well, but as I have not run this boat to any degree, I am just curious if my experience is typical.

So, boat tops out at 30mph with full fuel and four people, about 2750 rpm on the 350hp 3126 cats, cruise about 2400 at 25mph.

Does this sound about right?

Also, at cruise speed, the boat really runs bow up. I mean, if I really lay into the tabs it will bring the bow down a bit, but I was surprised at the running attitude. I don't really feel that comfortable sitting in the helm seat at cruise, because visibility is obscured by the bow. My 3375 cruisers ran at a better angle.

Do I need bigger tabs? Should I be cruising at a higher RPM (I think not)?

Any opinions?

 

[marty51]

My numbers are very close to yours. I keep fresh water tank close to full. The weight up front helps with running angle. Also give it some tab and see how it affects rpm. On my boat it seems to get me up on top and not hurt rmp or mph.

Marty

 

[tobnpr]

Pretty typical for aft-cabin boats with a V-drive setup.
That's a lot of iron far aft...
Different boat, but I have to run full tabs all the time for the best running angle/speed.

 

[endless seas]

Make sure tabs are working correctly.

 

[Dani-Lu]

I have the same boat with 385hp cats. At cruise I run with the trim tabs almost fully down. The bow comes down nicely and you don't lose speed, in fact I generally gain a knot. But I baby her and generally cruise at 2250 to 2300 with 2800 at WOT. 2250 seems to sound best to me, like they can run all day and night, which I pretty much did for 2400 miles to florida and back. All your running numbers sound real good. Even if you get the WOT up a little more, I doubt you will see any more speed. Great boat!

 

[steve mac]

I agree with Dani-Lu. I have the same boat (hull) with CAT 3208s and at cruise speed the bow comes down nicely, to the point where I can sit down and drive. As someone else mentioned, check that your tabs are working properly.