180 Sportsman, what prop to get?

[Markdelz76]

I have a 180 sportsman with a Yamaha 115 4 stroke. I have an aluminum prop but looking to upgrade to SS. Does anyone know what pitch, etc to get? The one I have now is perfect as far as rpm’s go at WOT (5900)

also, does anyone have first hand experience going from aluminum to SS? Any benefits?

Thanks!

 

[CharlieFoxtrot]

I have a 180 Sportsman with a 115 also. I had a 13.25 x 17 aluminum on her and my sense was that it was a bit too big. I have a 13 x 17 SS now and it might have been made a tiny bit smaller when it got reworked. It is perfect for my boat. I kind of doubt it had much to do with aluminum v. SS though. I think these smaller boats are more sensitive to weight and load. When I had the aluminum on the gas gauge was not working and I tended to have a lot of fuel on board. Now I usually run it with less than 20 gallons so that is probably 200lb difference. I also have a trolling motor with 2 batteries so that add another 150 or so. The other day I got her up to 6000 rpm at 38.5 mph so I am pretty happy with that. If I lose some battery weight I might try the bigger prop again. If you're getting 5900 rpm now I would just stay with that size regardless of what material.

 

[seasick]

I have a 180 sportsman with a Yamaha 115 4 stroke. I have an aluminum prop but looking to upgrade to SS. Does anyone know what pitch, etc to get? The one I have now is perfect as far as rpm’s go at WOT (5900)

also, does anyone have first hand experience going from aluminum to SS? Any benefits?

Thanks!

All else being equal, a SS prop will have better performance under load. That is due to the fact that SS is stiffer and there will be less blade flexing.
SS blades can be made thinner also and that can improve performance too.
The cons for SS over AL is mainly cost and potential damage to the LU when you hit something. AL props will bend and break a lot easier than SS. So if your boating is in area where hard grounding or hitting things with your prop is commonplace, an AL prop might be a better choice financially.
The reality about props is that two different props with the same pitch and diameter and made from the same materials can have very different performance characteristics.

The real question is " What do you want to get out of a different prop?" Better hole shot, better trolling, better top end speed ect.? A prop can be optimized for a specific operation range, not across the board

 

[Fishtales]

GW has some performance bulletins on their website. Might be best to see a local prop expert and try a few. As seasick states, SS is the way to go. Maybe an Al as a spare if you want one.