Re: smart tabs affect on top speed?
After 10 years, after selling thousands of Smart Tabs, after numerous Tests by magazines, invidiuals, and even boat builders (Larson/Volvo) we can most often get the tab adjustment tuned so that there is an increase in top speed. In fact it is rare that we don't see an increase. However it is important to understand why there is an increase in speed. The increase comes from being able to adjsut the running attitude of the boat, eliminate the porpoising, and adjsut the prop angle (TRIM) to get the best prop "bite".
Without trim tabs most boats will porpoise when the trim is moved to a vertical position (most efficient for prop bite). When trimming the motor down (NEG) to eliminate of minimize the porpoising you increase prop slip. By using trim tabs to control porpoising, and ride the prop is left to do it's job of propelling without compromise.
The preference of Helm controled tabs vs. Smart Tabs should be made by the owner based on his use of the boat and personal preference.
One of the posts indicated that the Smart Tabs would always limit top speed because the water pessure on the tabs would cause resistance, actually it causes lift which means a bit less boat in the water, enough bow pressure to eliminate porpoising, and a more controlled ride like the suspension system on your car.
Helm controlled tabs can eliminate porpoising with a slight deployment which increase stern lift and resulting bow down pressure. It is important to make sure you do not deploy the tabs too much as this will push the bow down more than necessary. (This would be the similar to an improper pressure adjustment on Smart Tabs). Small adjustments when at cruising speeds is the name of the game.
