Is my boat performing adequately? Smart Tab rigging?

lazypp

Cadet
Joined
Jun 26, 2010
Messages
20
I'm new to boating, so my apologies for my ignorance. I have an 04 Ebbtide 210 Campione deckboat. It has a Volvo Penta 5.0 Gxi/SX, 270 hp. I believe it weighs in at a little over 3000 pounds and we normally have a pax and fuel load of around 1000 pounds. I bought it with a 3 blade, 21 degree pitch prop that powered the boat to about 40 mph (GPS) and only 4200 rpm. I replaced that with a 4 blade, 14.5 x 17 degree Solas aluminum prop. Now I'm getting the desired 5000 rpm, with a speed of 45 mph.(GPS)
I added SS Smart tabs at the same time, and the holeshot and minimum planing speed is considerably better than with the original prop.
I am disappointed in the top speed (I saw a post from a similar Ebbtide owner that his max speed is mid 50's), and am also surprised by a couple other issues that I find surprising (But remember, I'm new to this boating thing)
First, the boat runs best with the trim fully down in all situations, with a very small speed increase (1 mph maybe), if I trim up just a twitch in some situations. If I do trim up however, a moderate turn will unload the prop and zoom the engine, which I find surprising. It makes me wonder if maybe the trim is not lowering as far as it should. A close look at the mechanism looks like it is lowering fully. My Seloc manual makes no reference to tilt/trim mechanical adjustment.
Secondly, I don't know how to make sure my Smart Tabs are dialed in. I've moved the "force" position up and down the length, and I'm not sure I'm seeing a difference. Should I be sharp enough to detect a difference in hole shot relative to hole positon on the tabs, or should I try to determine the position that equates to max speed?
Should I disconnect the tab and find top speed, then reconnect the tab and position the shock at the final position that still allows that top speed? (But don't they say the tab will actually increase top speed?)
My goal is to try and get the most out of the tab, but not push it to where I've got speed brakes constantly deployed.
Thanks for your insight,
Dan
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: Is my boat performing adequately? Smart Tab rigging?

Yeah . . . I think you should start without the tabs and see if we can get some trim up. My guess is that you are bow heavy on weight balance.

Why did you get the Smart Tabs? As a qualifier, I think all V-hull should have tabs, but why did you get them?

You should be able to trim up and get to the point of porpoising which is a rhythmic bouncing of the bow. If you can't (without the tabs) then she is probably bow heavy and you should shift some weight aft.

Also, I think you'll find the 17 to be too little pitch. Because I am lazy, what's the WOT RPM range? I am thinking with trim you will be well over ;) When all is said and done, maybe a 19 stainless if the loads are typical.
 

lazypp

Cadet
Joined
Jun 26, 2010
Messages
20
Re: Is my boat performing adequately? Smart Tab rigging?

Thank you for your response.
The WOT placarded range is 4600-5000, and with the new prop I am now getting the 5000 at the max speed of 45 mph (gps).
Why I purchased the smart tabs is a good question. I made a post here, titled "Hydrofoils/Stabilizers Good or Gimmick?" after wandering through a boating store and reading the amazing propaganda about a hydrofoil. The responses, as well as all the forum information I could find, indicated essentially nothing but positive benefits with smart tabs. I remember one post that said "Every boat is deserving of Smart tabs." It seemed like the perfect answer to a better hole shot and a slower planing speed.
I do confess that the new prop and the smart tabs have given me considerable improvements in both those aspects, but since they were installed at close to the same time I don't know fully which gets the most credit. And for that same reason, I don't know how to tell if my tabs are truely "dialed in" for best performance.
With respect to the bouncing of the bow, I'll try to make that happen next time I go out. It seems to me that when I've raised tilt before it just goes to a point where its unloading the prop and zooming the engine, which is a point very close to what I think is best cruise trim position. I'm a rookie though, so what do I know?
Thanks again!
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: Is my boat performing adequately? Smart Tab rigging?

A lighter bow allows higher trim settings, but may introduce porpoising. The fastest setup for most boats is a light enough bow to allow porpoise with full up trim and then control of the porpoising with trim tabs. Good luck! My guess is you will be above your WOT range with the 17 after getting the bow up more ;)
 
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