SX Smart Tabs Trim Tabs for Boat Length 9-1/2" x 10", 13'-15' , 30-40hp 2-Stroke Outboard - Nauticus

Tabs were easy to install and did a great job on my boat! Great price and quick delivery! Highly recommended! My boat rides so much better with the tabs!

I have a small 13' aluminum hull shallow-vee RIB with a 35hp 3-cylinder Evinrude that I wanted to see if I could reduce the porpoising and wave handling. I purchased the smallest one using the selector tool as I have relatively small motor and very light boat. As I didn't want any stainless hardware reacting with the aluminum hull below the water line I mounted these to large aluminum plates (very stiff) and installed the retracting kit as well. I removed the Attwood Hydro-Stabilizer (bolt on hydrofoil to the anti-ventilation plate) and fixed up the empty bolt holes as directed. After installing (which took awhile as I wanted everything to be square/sealed/etc) I went through testing the five different settings on the Smart Tabs with each of the five different trim settings I have on the engine. Unfortunately with no setting was I able to reduce the porpoising over the hydrofoil alone, and even with the plates on minimum (or retracted) and the engine fully tucked in, I always have significant ventilation issues in corners without the hydrofoil. For getting to fishing holes it's not so important but cruising or water sports I can see it being quite significant. My time to plane is slightly higher, but I can hold plane at about 13mph vs 15mph. Efficiency isn't noticeable over 2 tanks (100L) but my top speed seems to be slightly less (1-2mph). They are always in contact with the water so I would imagine they have more drag at high speed than a hydrofoil that lifts out and runs dry at high speed. It seems like more work with both installing (which required me to move my transducer, speed and temperature sensor) and limits my mounting for an electric trolling motor. Also, I should be retracting them with putting it on the trailer and it's more likely to wear down if the seals go. I do see issues with the hydrofoil as well (damage to the anti-ventilation plate, holes in the engine to mount, force on the motor/transom which I personally think is negligible compared to the weight of the motor) but overall so far they seem better. I will try a larger anti-ventilation plate later. I could see them being beneficial on stern-heavy deep-vee boats that squat and have issues getting on plane, but for the small light boat I have, I don't think they're the best solution.