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Old 05-05-2008, 11:36 AM
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Currently running a 08 33 daytona with 700 Mercs NXT drives. Heres the numbers- 131.9 mph on the rev-limiter with 1.35 gear, 39 pitch merc cnc 16.25 diameter with a 21 rake.136.9 mph on the rev 40 pitch merc cnc 16.5 diameter with a 18 rake.
With 6 200 lbs.+ guys full gas 2 coolers it would run 125 on the rev.with the 39's.
With the 40 pitch it handled real flakey with a load. Would hardly get on plane with the load.
My question is there a better prop we can run with the larger pitch to keep the same driving capabilities and planning as the 39 pitch props.
The X demension is high on this boat and the hull has been changed there is no porpoise on flat water and carries the nose like no other eliminator I have seen.
Also is there a less expensive prop that will work on these drives when we run in shallow lakes?

Any Help would be great! Thanks Ryan
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Old 05-05-2008, 08:37 PM
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11% slip with the 39.
7% with the 40.
Both very good.

More stern lift occurs with the additional diameter and pitch and the decreased rake...............

Increase pitch, decrease diameter and add the rake. 16.25x40 21degrees. Don't tell everyone, I'll be out of a job.
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Old 05-07-2008, 09:54 AM
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Lol from what I hear your not going to be out of a job! I guess I am wondering if the 40's 16.25 21r will get on plane as well as the 39's. It was a serious struggle to get on plane. Could this be due to the rake? Why is it harder to get on plane with larger the pitch? And the 40's we tried were 16.5.
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Old 05-09-2008, 08:21 AM
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Originally Posted by B BOATER
Lol from what I hear your not going to be out of a job! I guess I am wondering if the 40's 16.25 21r will get on plane as well as the 39's. It was a serious struggle to get on plane. Could this be due to the rake? Why is it harder to get on plane with larger the pitch? And the 40's we tried were 16.5.
Good question, wondering myself. Could it be the amount of foil in the front of the blades??
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Old 05-09-2008, 12:28 PM
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Just dont understand why its harder to get on plane with a prop thats larger in diameter and less rake with more pitch.
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