5 blade for midrange performance?
07-16-2012, 06:25 AM
#1
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5 blade for midrange performance?
I spoke w/Cutting Edge props in California about maximizing mid range performance on my 30' w/mag HO's and his recommendation was to use a 5 blade, down 1" in pitch and maybe a little tuning to get the max RPM is line. Agree...disagree.
07-16-2012, 06:41 AM
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Agreed, 5 blades are more efficient, especially noticable at cruise speed.....less rpm to maintain the same speed as 4 blades.
Everytime you add a blade, you drop a degree of pitch.
I just had Cutting Edge work my Hydromotive 5 blades with excellent results.
I have not tried their own design of props but will definately do it in future applications.
Everytime you add a blade, you drop a degree of pitch.
I just had Cutting Edge work my Hydromotive 5 blades with excellent results.
I have not tried their own design of props but will definately do it in future applications.
07-16-2012, 02:09 PM
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I'm thinking stock 5 blades will work, really no need to Lab them.
Having said that one thing to keep in mind is that the 5 blades will add a small amount of stern lift, which may effect handling as you know it with the 4 blades. (It may not be dramatic)
The best solution would be to have the props tweaked with some cup to help pull the bow up a bit and offset the stern lift.
I'm sure the professionals will chime in.
Once the 5 blades are set up you will leave the 4 blades on the shelf, night and day hole shot, mid range cruise and punch...just my 0.02....
Having said that one thing to keep in mind is that the 5 blades will add a small amount of stern lift, which may effect handling as you know it with the 4 blades. (It may not be dramatic)
The best solution would be to have the props tweaked with some cup to help pull the bow up a bit and offset the stern lift.
I'm sure the professionals will chime in.
Once the 5 blades are set up you will leave the 4 blades on the shelf, night and day hole shot, mid range cruise and punch...just my 0.02....
07-16-2012, 02:56 PM
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Agree.......I dropped slip down to 10.5% when I went to 5 blades. I had been running 32P 4 blades for years and made it about 25 hours with 5 blades and lost a drive. Sold the boat soon after (coincidence) and the new owner lost a drive about 25 hours later. They have better mid-range because they bite the water much better. If you surface them and have too much power you are more likely to break something (I made 700 ft/TQ full dressed)
07-16-2012, 03:29 PM
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I just drank the cool aid and ordered a set from cutting edge well see how they work I already had good slip numbers right around 9% not super concerned about all out speed just safety and drive ability
