Proping question...
#1
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Ok, tell me what your thoughts are on my current setup...
26' Cat w/600hp. I'm running an extension box with a imco shortend lower. The ratio is 1.5.
30" stock Bravo 1 @ 5,000 rpm = 85mph
32" stock Bravo 1 @ 5,200 rpm = 90mph
34" lab Bravo 1 @ 5,500 rpm (red line) = 87mph
What should I try next? If you look at the slip numbers, they are all too high. I think the 32" is the best at 15%. The 32" should have me just under 100mph, and the 34" well over. I'm also curious as to why the higher pitch props rev higher and go faster. Seems kinda contradictory. I'm seriously thinking about going to a 1.36 ratio and some lower pitch props.
26' Cat w/600hp. I'm running an extension box with a imco shortend lower. The ratio is 1.5.
30" stock Bravo 1 @ 5,000 rpm = 85mph
32" stock Bravo 1 @ 5,200 rpm = 90mph
34" lab Bravo 1 @ 5,500 rpm (red line) = 87mph
What should I try next? If you look at the slip numbers, they are all too high. I think the 32" is the best at 15%. The 32" should have me just under 100mph, and the 34" well over. I'm also curious as to why the higher pitch props rev higher and go faster. Seems kinda contradictory. I'm seriously thinking about going to a 1.36 ratio and some lower pitch props.
#2
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Slip--30"=10.25%
32"=14.3%
34"=26.3%
That's what I've been saying all along--The smaller pich around 26-28" are the most efficient slip wise.
So if you use 1.36 and 28" and 7%slip if you turn 5300rpm that equals 96mph.
32"=14.3%
34"=26.3%
That's what I've been saying all along--The smaller pich around 26-28" are the most efficient slip wise.
So if you use 1.36 and 28" and 7%slip if you turn 5300rpm that equals 96mph.
#3
speel chekk this fokker!
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yeah tht seems very wierd with rpms increasing with diamter.
wel maybe not. YOu slip numbers are goign up. Myeb eth larger props just aren;t as efficient as the smaller one and wont; hookup. I have 5 blade 30p herring. if your interested. Its for a big shaft bravo. hering was goignt o trade me a 27p for small shaft for it. its brand spankin new and a damn nice wheel!
i'm running 29p lefty and i really liek the way that it runs. much nicer than a merc prop.
wel maybe not. YOu slip numbers are goign up. Myeb eth larger props just aren;t as efficient as the smaller one and wont; hookup. I have 5 blade 30p herring. if your interested. Its for a big shaft bravo. hering was goignt o trade me a 27p for small shaft for it. its brand spankin new and a damn nice wheel!
i'm running 29p lefty and i really liek the way that it runs. much nicer than a merc prop.
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#4
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Cobra-you confirmed what I was suspecting. I need more pitch, but the efficency was getting wacked. Sounds like a regear is in order!