Slight difference in diameter – 14″ vs 14 5/8″ IIRC. (Fury first). Difference in blade shape (rake, cup, progressive pitch change, etc.) Much stiffer Alloy. When the Tempest + came out, it was the go-to prop until the Fury came along. It now seems to be king of the hill unless you run a heavier boat. Im certainly a big fan of it.Urban legend says the fury likes to run deeper than the tempest. Not exactly true. It really likes the blade tips to run at exactly the same depth as the Tempest, but that means about 5/16″ lower since the blades are 5/16″ shorter on each side.