Impeller Calculator

Jet Drive Horse Power Chart, These traditional charts, and our Tech help will help to decide on an Impeller "cut" for your jet drive. Please note that not all boat hulls, jet drives, and engines will "like" or benefit from the applications as indicated, there is a significant amount of science to this process but also trial and error are often necessary to get the exact, best or optimum Impeller application.

A multitude of factors come into play when choosing impellers: Actual (or estimated) Crankshaft Horse power and Torque as well as the RPM range where HP&TQ are made are vital, altitude of operation is very important! Also the boat hull size and weight as well as the intended usage application (eg pleasure/river cruiser, Race boat, utility boat etc). The type of Jet (Axial, Mixed flow, Multi-stage), as well as "hardware (loaders, shoes, etc.) will also change results. These "tools"(charts, etc.) are calculated using "known good" jets and optimum condition components.

The material of the impeller (Aluminum alloy, Stainless, Bronze) is typically chosen predicated on Horsepower and type of useage. Bronze and stainless alloys are stronger and are recommended for use when Horsepower is above 450 to 500 range or useage is considered "severe".

The Charts and Our JBP Interactive HP Chart can also be used as a very useful "diagnostic tool". Example: (1*)If you know your HP (dyno results) and Impeller cut (A, B, C etc) a reference here should tell you what WOT* rpms should be close to, or....... (2*)with your actual known (accurate Tach) WOT RPMs along with your known Impeller cut & brand* may be able to provide an approximation as to the HP your engine is making. (3*) If you know your horse power (or accurately can estimate it) and you know your accurate WOT* rpms you can get a "feel" for your "unknown" Impeller cut and/or the health and efficiency of your jet drive.