Rake is an aspect of prop design that is not much discussed but it can be very important to your boat's performance, or can correct some of its bad habits. Rake is the degree that the blades slant forward or backwards in relation to the hub. For example, aft rake helps to trim the bow of the boat upwards, which often results in less wetted surface area and therefore higher top end speed. Forward rake helps hold the bow of the boat down. Once again, this is a matter for prop experts to figure out once you have given them the facts of your application.