prop diameter

tblshur

Senior Chief Petty Officer
Joined
Aug 24, 2011
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688
i have a general question . what effect on performance does going from a 13.25 dia prop to a 14 inch prop or would it be noticeable:confused:
 

Bondo

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i have a general question . what effect on performance does going from a 13.25 dia prop to a 14 inch prop or would it be noticeable:confused:

Ayuh,.... Generally speakin',..... Diameter has little to do with choosin' a prop,....

Diameter is determined more by blade design, 'n the prop's purpose,.....

Generally, diameter goes Up, as pitch goes Down,....
 

tblshur

Senior Chief Petty Officer
Joined
Aug 24, 2011
Messages
688
thanks guys, 3rd owner of 1983 ranger 330 with johnson 140 hp, j140tlcte, it has ss 19 pitch prop hole shot has never been much .was advised to try a 17 pitch , it was great. i had borrowed the 17 . as i was looking for one i saw a 14 inch dia , 17 pitch. i think my lu would have enough room for a 14 that is the reason i ask. thank you very much for your help:joyous:
 

SkiDad

Lieutenant Commander
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Jul 18, 2010
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i feel like the 14" diameter will have better hole shot b/c it will push more water, but slightly lower top speed due to drag. that has been my experience
 

tblshur

Senior Chief Petty Officer
Joined
Aug 24, 2011
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688
thank you mitzysman, the extra hole shot is what i need i can live with a little less top end. thanks again for your reply:joyous:
 

Tail_Gunner

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Jan 13, 2006
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Over-Hub Exhaust
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 are often used for attaining maximum top speeds.
On some vessels, the hole shot can often suffer due to the extreme exhaust flooding that occurs around the blades during acceleration.

info-exhaust3.gif



Over/Thru-Hub Exhaust
Over/Thru-hub exhaust propellers are a combination of thru-hub and over-hub exhaust.
This allows some exhaust to escape at lower RPMS, providing a controlled amount of exhaust flooding.
These types will allow the propeller to be slightly easier to turn during initial acceleration, allowing for a better hole shot on some engine/boat combinations.

info-exhaust2.gif


You will more than probably get more benefit from one of these design's
 
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tblshur

Senior Chief Petty Officer
Joined
Aug 24, 2011
Messages
688
Tail_Gunner very interesting and informative post . ive been learning alot about props, boats engines and their functions , love this forum. im not atourney fisherman just trying to not lug my engine. thank you very much for your post.:joyous:
 
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