Do I Need A 4-Blade Prop?
A lot of boat owners have a common misconception that 4 blade propellers deliver increased performance and are more efficient than 3 blade propellers. There are quite a few older forum posts and other guides that claim 4 blade props are needed when wakeboarding behind a ski boat or older model v-drive with a 1:1 gear ratio.
This was indeed the case a few years ago but all of that changed when Acme started the implementation of precision CNC Propeller manufacturing. Thanks to Acme Propellers the 3 blade is gaining the reputation it deserves. The Acme 3 blade prop has an awesome hole-shot with an unmatched top end speed. What is truly amazing is the smoothness throughout the rev range unlike the hand finished props of the past.
If your boat does have a gear reduction, typically 1.23:1 or 1.5:1, the transfer of the motor's power to the water will allow a 4 blade or even 5 blade propeller to obtain better performance. Reduction gears also provide the ability to run greater propeller diameters which in most cases are more efficient.
In short, the perfect prop for your boat is not determined by the number of blades the prop has. It is determined by how you use your boat (cruising, wakeboarding, slalom skiing, etc.) the elevation at which you are riding, your speed requirements, and the amount of ballast you are running in your boat.