If three blades are good, will four be better? To find out we ran the Revolution 4, sort of a four-blade cousin to the Tempest Plus designed to deliver better hole-shot acceleration than the Tempest simply because it has more blade area. The Rev 4 is very popular on twin-rig outboard offshore boats because it really holds well in rough water, especially in following seas that can lift the transom and ventilate the prop. Merc also recommends the Rev 4 for stepped-hull boats, which send a lot of frothy, aerated water to the props. The extra blade should also produce more drag and thus lower top speed. That might be true on a faster or heavier boat, but in a more modestly powered rig like ours, the difference in performance between these two props is negligible. That said, the Rev 4 feels great from the helm. There’s pronounced bow lift at the last 5 percent of the trim range, it holds well in turns, and it offers better reverse thrust than the Tempest Plus. For general-use boating, overall smoothness is the key advantage of a four-blade prop.