Talkin' Tab

[gw204]

I noticed there is a thread or two in which some of you have expresesd dissatisfaction with the performance of your undersized tabs. So, I felt obligated to offer my comments and experiences on this very subject.

Many of you know that I used to run a 204 Grady center console. It was originally purchased without tabs and I added a set of used Bennett 12x9s. They were $100 and I couldn't pass them up. This addition did help the boat's handling quite a bit, but over time they proved to be inadequate.

Based on my converstaions with Tabman, I ordered a new set of 12x12 trim planes. These mounted in the existing holes left by the 12x9s and line up perfectly with the actuators. Installation was very simple and required no modification to the hydraulic or electrical components. The extra 3" of chord these new trim planes offered was a drastic improvement, but I still wanted better without having to do drill any more holes in my transom.

So, I again contacted Tabman as I had an idea rolling around in my head. My idea was based on the "bat wing" design of the current sport tabs. I wanted to find out if I could have some sort of fins fabbed up and bolted to the existing 12x12 planes. Wouldn't you know it, Tom already had a solution for me in the form of Bennett Drop Fins. After I bolted these babies on, those tabs did exactly what I wanted. There was absolutely no water lost out the sides and performance was nothing short of perfect!

I highly recommend these to anyone looking to improve the performance of their trim tabs!!!!!

 

[DaleH]

I'm glad that retrofit worked for you and that Bennett Marine helped you out ... but ...

Performance ... yes

Efficiency? ... no

No offense, but that's why in the posts about tabs I recomend the minimum of the 24" wide by 9" deep tab plane. Smaller tabs will "work", like the stock Lenco 12" x 12" planes, but you will LOSE 10-20% miles-per-gallon efficiency over the same hull/motor combo if you had used the larger planes to give you the same bow angle.

That is the main point I have been trying to hammer home on people looking for alternate tabs.

 

[Megabyte]

I think what Brian was working toward here, was applying the principal of the Bennett "Sport Tabs" (which are a 'bat wing' design), to the tabs he already had, which were admittedly smaller than he wanted.

The M80 and M120 designs have the 'drop fins' which (according to Tom), cause the narrower planes generally applied to smaller vessels to have more 'lift' due to the channeling action of the fins.

What Bennett came up with, is a set of aftermarket 'fins' that could be applied to any size tabs (even our big flippers ) and cause even greater lift. The 'wings' channel the water energy so that it doesn't slide out and become lost. An interesting concept, especially for folks who don't have the transom space to apply wider tabs.

Kudos to Bennett for coming up with solutions like this.

 

[gw204]

Bingo Kev! The intent here was to show others that upgrading to wider tabs is not the only option to get better performance out of tabs that are already installed. Were these the best option? No, and I already knew that. But no. 1, I didn't want to be drilling any extra holes in my boat and no. 2, I didn't have the space for anything wider. What you don't see on the other side of the transom is a transducer that must maintain a certain distance from the engine. A wider tab would have thrown that all off...

Did these drop fins increase the efficiency? Absolutely. Prior to installing them, I had to put the tabs much further down to get the same effect as using a little tab after the installation. More tab caused a more drastic decrease in speed and increase in fuel consumption, as verified by GPS and fuel flow meter. Would they have been as efficient as an 18x9? Who knows.

The bottom line is any set of tabs that get fitted with these drop fins will work better than tabs of the same size without!