4 blades -vs- 5 blades
#1
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From: The Woodlands, TX
Alright it's me again with another newbie question.
One of my buddies tells me I'll pick up some cruising speed but put more load on the drives with the same pitch and lose some top end while another says drop an inch of pitch and you'll get better fuel consumption at the same cruising speed and top end speed will remain about the same. I would think it would take more rpm's to keep the same speed with less pitch and you would lose speed or hit the same at a higher rpm.
I'm curious as to who runs 5 blades and what your experiences have been with them, and do bigger boats favor more blades?
See ya,
Kelly
One of my buddies tells me I'll pick up some cruising speed but put more load on the drives with the same pitch and lose some top end while another says drop an inch of pitch and you'll get better fuel consumption at the same cruising speed and top end speed will remain about the same. I would think it would take more rpm's to keep the same speed with less pitch and you would lose speed or hit the same at a higher rpm.
I'm curious as to who runs 5 blades and what your experiences have been with them, and do bigger boats favor more blades?
See ya,
Kelly
#2
You will get the best top speed with the least blades. You will get the best cruise speed with more blades.
If you run a high X then you need more blades to get on plane and to get back the cruise speed you lost from raising the drive. More blades will be less eficient but the slip will go down.
If you run a high X then you need more blades to get on plane and to get back the cruise speed you lost from raising the drive. More blades will be less eficient but the slip will go down.
#5
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You really don't have the power or the high x dimension to turn a five blade. Plus they increase stern lift. To get the rpm you need to turn the 5 blades would be very low pitch. In perf boats a 5 blade is good if you are close to or are surfacing. Your Baja's x dim is not that high so you would run them submerged. Your whole shot would be insane but top speed would be horrible.
#6
I have had good results changing from Bravo 1 4-blades to Maximus 5-blades. Ask yourself this question, "Where do you spend the majority of your throttle time, WOT or cruising?" If you are a WOT guy stick with your best 4-blade. If you are spending the majority of your time in the "cruise" mode, the 5-blades will be helpful. I picked up 4 mph at 3500 rpm using the 5-blades. That translates to higher mpg and fuel savings to me. I always throttle up gently as you can feel the 5-blades "bite" firmly as the boat comes on plane. I did loose 3 mph on top end, but that is ok with me. If I choose to run fast, I will temporarly install the 4-blades for the day.
#7
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I have had good results changing from Bravo 1 4-blades to Maximus 5-blades. Ask yourself this question, "Where do you spend the majority of your throttle time, WOT or cruising?" If you are a WOT guy stick with your best 4-blade. If you are spending the majority of your time in the "cruise" mode, the 5-blades will be helpful. I picked up 4 mph at 3500 rpm using the 5-blades. That translates to higher mpg and fuel savings to me. I always throttle up gently as you can feel the 5-blades "bite" firmly as the boat comes on plane. I did loose 3 mph on top end, but that is ok with me. If I choose to run fast, I will temporarly install the 4-blades for the day.
#8
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Joined: Apr 2008
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From: Sudbury Ontario
The Hydromotive PX-5's have less flare on the diffuser ring to eliminate stern lift.
Stepped hull boats were designed to run flat and the 5 blade over 4 blade props work very well. Stepped hulls do not like stern lift as the already run flat....
I have run both 4 blade Bravo1's and the 5 blade Hydro's and prefer the 5 blade Hydro's. Easier to plane and better cruise speed/rpm.
Stepped hull boats were designed to run flat and the 5 blade over 4 blade props work very well. Stepped hulls do not like stern lift as the already run flat....
I have run both 4 blade Bravo1's and the 5 blade Hydro's and prefer the 5 blade Hydro's. Easier to plane and better cruise speed/rpm.
#9
The Hydromotive PX-5's have less flare on the diffuser ring to eliminate stern lift.
Stepped hull boats were designed to run flat and the 5 blade over 4 blade props work very well. Stepped hulls do not like stern lift as the already run flat....
I have run both 4 blade Bravo1's and the 5 blade Hydro's and prefer the 5 blade Hydro's. Easier to plane and better cruise speed/rpm.
Stepped hull boats were designed to run flat and the 5 blade over 4 blade props work very well. Stepped hulls do not like stern lift as the already run flat....
I have run both 4 blade Bravo1's and the 5 blade Hydro's and prefer the 5 blade Hydro's. Easier to plane and better cruise speed/rpm.




