Yet Anouther Dum Question On Size

[Boss Hawg]

I'm looking for another prop for my 1987 16' Starcraft fiberglass Bassboat running a 1987 70hp Johnson - It has a 13 1/4 x 17 prop now-
I see everything from 13, 13 1/4, 13 1/2 up to 14 x 17 props all with 13 splines all claming to fit the same motors
I understand pitch & number of splines but where does the hub size come into play & why the difference & still fit the same motor

 

[steelespike]

Re: Yet Anouther Dum Question On Size

I believe the 14 is intended for oversize gearcases and I/Os.
You'll note

 

[Dhadley]

Re: Yet Anouther Dum Question On Size

The different diameters can mean several things depending on the manufacturer. Typically the props for your motor are 13 1/4" in diameter. Some 4 blades might be a little less diameter. Some performance props may be slightly larger in diameter like the old OMC Raker in 13 1/2" and the Turbo Lightning Jr also at 13 1/2. Some 4 stroke specific and pontoon specific props are in the 14" diameter. A 14" diameter prop is about as big as you can go on your motor.

All those props do something different. The trick is to decide on what you need a prop to do and then seek out those characteristics.

 

[Boss Hawg]

Re: Yet Anouther Dum Question On Size

Thanks to both ya'll-
Wow, my last boat was about the same size/style but had a new SS prop & i never had to worry about changing it
BTW, i think the prop that was a 14 had a 19" pitch I was seriously concidering it because i was told it would bring me to plane quicker & give a bit more top end - Now i'm running about 40mph @ 5500 rpm's