Re: How much will a whales tail help a 25hp?
Wondering if your boat, being small and light, is tiller steering, or remote? In other words, does it have all the weight at the stern?<br /><br />Sure, a fin on the anti-cavitation plate will be a big help, but it has several disadvantages. The fin angle is tied to the propellor angle because both are fitted to the same leg. Fins often work better with slight negative trim, and this means that the propellor will also be operating ‘out of square’ with the water. Additionally, because the fin is central to the hull, it cannot provide optimum port/starboard stabilisation of the boat, as trim tabs can. As it does not follow the deadrise angle of the hull, it is also a permanent additional source of underwater resistance. The enlarged horizontal surface of the fin can also cause the boat to be less responsive in turns.<br /><br />The most effective answer is to keep propulsion and trim functions completely separate. The function of the propellor is to drive the boat forward, and it can only do this with maximum efficiency when it is at right angles to the water. Obviously if you can fit tabs instead of a fin, you'll get even better response.<br /><br />End of commercial.
