Re: mercury prop size
Bow-lifters tend to have more "rake" (blades angle more aft) and significant cup around the tip. A stern lifter has less rake (blades are closer to 90 degs to the hub, and are cupped at the trailing edge only, if cupped.<br />The bow-lifter in the right application allows more bite at higher trim levels to lift bow and decrease wetted surface area, increasing speed.<br />Some boats don't react well to bow-lifters, and tend to porpoise, this is where a more standard stern-lifting type prop does better.<br />Most high performance Bassboats use bow-lifters, and most deep-V's using higher power outboards run best with a prop that is in-between, and a cruiser, or heavier deep-V (slower) will use a stern-lifter.<br />I have an 18ft alum Deep-V with a 200 that runs real good with the "In-between" props with less aggresive rake, but reacts good to moderate cupping. If I mount up a high-rake bow-lifter, it won't hold the bow up as much due to hull design, and I can't utilize the props capabilities, therefore losing some efficiency.
