5 blade vs. 4 blade prop
#1
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5 blade vs. 4 blade prop
How do you know when your application would benefit from a 5 blade prop? Is there some general rule or should you always just test both to be sure?
#2
Re: 5 blade vs. 4 blade prop
If you're having trouble getting on plane with a 4 blade a 5 blade can help, also if you have high prop slip at mid-range speeds again a 5 blade can benefit by reducing the slip resulting in more speed. Typically a 5 blade will not be as fast on top end, but will make up for it in all other areas. I went to 5 blades and I'm very happy with their performance.
#4
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Re: 5 blade vs. 4 blade prop
We tried them on our 35 Fountain, we saw the same as what Harper discribed. Got on plane easier, cruised 3-5 mph faster in the mid range, 3300-3800 rpm, but was 4 mph slower on the top end than the 4 blade. That was running Hydromotives P5 and 4 blade. Hydromotive said they can get the 5 blade as fast as a 4 blade but it would require labbing, deffusier ring adjustments ect. Have heard both that they are harder on drives and easier. Easier because they have less vibration because more blades in the water at once, and harder because they dont slip as much. Currently have 5 blade Maximus on our 38 Fountain with shorties, will start experimenting with props when the weather warms up a little. The biggest gains are in high slip applications, like cats with very high X's and when the blades are sufacing. If your props are not surfacing, its hard to beat a 4 Blade.
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Re: 5 blade vs. 4 blade prop
Thanks for the information. The reason I am asking about 5 blades is because I am considering 2"shorties. Even with the x-dimension higher do you think that 4 blades will have the better top speed. Do the 5 blades make up for the slippage?
#7
Re: 5 blade vs. 4 blade prop
Originally Posted by Rebel_Heart
Thanks for the information. The reason I am asking about 5 blades is because I am considering 2"shorties. Even with the x-dimension higher do you think that 4 blades will have the better top speed. Do the 5 blades make up for the slippage?
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Re: 5 blade vs. 4 blade prop
The 5 blades are slower at top end but better at mid range and getting on plane as stated earlier,they raise the drives with the 5 blades to acheive similar top end as the 4 and still get on plane and have a better mid range.The 4 blade would probably be better at top end with a higher drive but you would't be able to get on plane
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Re: 5 blade vs. 4 blade prop
Sounds as though I'll stick with the 4 blade for top end. I, too hope that I will pick up speed by going higher because I know I will have more slip. Guess there is no way to find out except by experimenting. Just trying to save some $ on the shorties if there is not speed to be gained.
#10
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Re: 5 blade vs. 4 blade prop
You guys keep this up and you won't need us on the board anymore. All very good information.
Testing is the only to ultimately know what will work the best for your set up. Maintaining the best efficiency with low drag is the key!
Testing is the only to ultimately know what will work the best for your set up. Maintaining the best efficiency with low drag is the key!
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Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]