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Horsepower VS Gear Ratio question

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Old 08-26-2015, 12:56 PM
  #11  
SB
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As a general rule of thumb that I've been told is:

There is a near perfect prop for each boat. You just have to find what that is, then gear accordingly.

Sounds a lot simpler than it is...lol.

Edit in: Obviously, boats that have lower numeric gears than 1.5 are because they ran out of pitch availability.
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Old 08-26-2015, 02:26 PM
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Originally Posted by JRider
How does spinning the props faster affect lift? Would it increase stern lift?

I am asking because I am looking at a boat with 1.24 drives and it needs as much stern lift as possible.

BTW, Mercury only recommends gear changes when there are no available prop pitches left.
This would support the information that I have always been told. I don't claim to know alot about set ups, but I do have access to some really smart experienced people who also suggest this thought process.
I do think from experience that it is much easier on the drive to do this as well, You are basically making up for heavy torsional loads with RPM. Which is really good with Bravo set ups.
As far as lift, I believe it has to do with the number of times the blades are intering and leaving the water. the more the more lift you will get. Obviouisly blade rake and rotation have a larger factor on lift.
As far as pitch goes, you can get very effiecient props up to at least 38, maybe even higher. So unless your above that, it is a mute point. I am sure the prop gurus could give us alot more info on that.
This is just what I have been taught and seen on my boats and so far it all seems to hold true.
As far as a perfect pitch for each boat. I know yrs ago when CRC was dominating the cat lights. They had a set of 38 Herrring they loved so much they would split gears, topand bottom on their 6's just to use those wheels when they had an arsenal of other props and gears. lol
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