Propeller Characteristics - Exhaust
|
|
What is the difference between thru-hub exhaust, over-hub exhaust, and non thru-hub exhaust?
Thru-hub exhaust propellers consist of a round barrel to which the blades are attached. The exhaust passes through the barrel and out the back, without making contact with the propeller blades. This provides a good clean water flow to the blades, usually resulting in good acceleration and hole shot.
|
|
Over-hub exhaust propellers have the blades attached directly to the smaller tube that fits over the propeller shaft, eliminating the larger exhaust tube. These types of propellers are often used for attaining maximum top speeds. (On some boats, the hole shot can often suffer due to the extreme exhaust flooding that occurs around the propeller blades during acceleration.)
|
|
Over/Thru-hub exhaust propellers are a combination of thru-hub and over-hub exhaust propellers. This allows some exhaust to escape at lower RPMS, providing a controlled amount of exhaust flooding. These types of propellers will allow the propeller to be slightly easier to turn during initial acceleration, allowing for a better hole shot on some engine/boat combinations.
|
|
Non thru-hub exhaust propellers are used for inboards using shaft driven propellers, sterndrives using through hull exhaust, and on some outboards that don't route the exhaust through the lower unit torpedo.
|
|
|
Learn All About Propellers Here!
|
Propeller Basics
Prop Characteristics
Determining RPM's