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Prop/reduction Help

L

lcox77

Member
I have a mild small block Chevy on a 13ft aluminum hull and currently have option for a 2-1 or 2.3 belt reduction, looking for prop recommendations and reduction ratio. Mostly using the boat for riding, hunting, etc and would like to run dry not looking for a ton of top speed. Thank you
 
Unfortunately my cage is only 80 inches wide, I’m trying to put everything together without building a new cage but I’m afraid I might have to
 
lcox77 said:
Unfortunately my cage is only 80 inches wide, I’m trying to put everything together without building a new cage but I’m afraid I might have to
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Yah, understand, anything over 74" prop is starting to push it, 76" hard max for sure. The engine probably makes 250-300 Hp at best at 5,500 RPM unless it has been worked. 2,750 prop speed with 2:1 or 2,400 at 2.3:1.

The 2:1 works and there are props that will work well without changing the rigging, but the 2.3 with larger 78-80" blades will give you more push (5-10%??). You should talk with the prop manufacturers about 74-76" options on the 2.3, unfortunately the selection is limited without buying a cut down version of a larger blade.

If you have any thoughts of upgrading the engine going forward, then the 2.3 and room for 80" of prop is the place to start. Note that you can always add blocks to raise the rigging and weld in horizontal sections to make it wider vs. starting over.
 
Slidin Gator said:
Yah, understand, anything over 74" prop is starting to push it, 76" hard max for sure. The engine probably makes 250-300 Hp at best at 5,500 RPM unless it has been worked. 2,750 prop speed with 2:1 or 2,400 at 2.3:1.

The 2:1 works and there are props that will work well without changing the rigging, but the 2.3 with larger 78-80" blades will give you more push (5-10%??). You should talk with the prop manufacturers about 74-76" options on the 2.3, unfortunately the selection is limited without buying a cut down version of a larger blade.

If you have any thoughts of upgrading the engine going forward, then the 2.3 and room for 80" of prop is the place to start. Note that you can always add blocks to raise the rigging and weld in horizontal sections to make it wider vs. starting over.
Click to expand...
Thank you for the help! I appreciate it
 
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