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  1. #1
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    SHO / Tempest ??

    Recently went from a 25P Mercury Tempest A45 (flung an ear) to a newer A47 - the hole-shot & top end (71.5) are the same but the RPM's on the A47 max out @ about 5600 (can't get it higher) whereas the older A45 reached 6000.


    Any ideas why ? No motor adjustments etc. made between prop swap.


    Thanks
    2024 Z520R / 2022 250 ProXS

  2. Member
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    Jan 2005
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    #2
    The older A45 was slipping more than the newer A47 15% versus 10% for the new one. The blades on the older models were a little thinner than the new ones to keep them from cracking. If you want more speed and rpm's have the prop B&B by Mark Croxton.

  3. Member
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    #3
    Quote Originally Posted by mdtritn21 View Post
    The older A45 was slipping more than the newer A47 15% versus 10% for the new one. The blades on the older models were a little thinner than the new ones to keep them from cracking. If you want more speed and rpm's have the prop B&B by Mark Croxton.
    Thank you sir! I will check out the possibility of sending it over to Marks shop.
    2024 Z520R / 2022 250 ProXS

  4. Moderator 21XDC's Avatar
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    Sep 2004
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    #4
    I'd consider trying a 23P Tempest Plus before you have any work done to the 25P.

    Marks Props 317-398-9294, 1850 East 225 South, Shelbyville, Indiana 46176 propellerman59@gmail.com http://www.marksprops.com/index.html

  5. Member
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    #5
    Quote Originally Posted by 21XDC View Post
    I'd consider trying a 23P Tempest Plus before you have any work done to the 25P.
    thank you ... and if I might ask: why do you recommend a 23p vs 25p ?
    2024 Z520R / 2022 250 ProXS

  6. Moderator 21XDC's Avatar
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    #6
    You need more rpms than Mark can get you from your 25P

    Marks Props 317-398-9294, 1850 East 225 South, Shelbyville, Indiana 46176 propellerman59@gmail.com http://www.marksprops.com/index.html

  7. Member
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    #7
    Quote Originally Posted by 21XDC View Post
    You need more rpms than Mark can get you from your 25P
    thank you for clarifying/ explaining ... I’m a bit of a prop novice having just run a 25p for awhile.
    2024 Z520R / 2022 250 ProXS