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  1. #1
    BlackHawk's Avatar
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    Prop question...lost over 1000 RPM's

    I had Skat trek pitch my three bladed prop to a 15/19.5 ran it with a 81mm nozzle ring...was barely hitting 7300 rpm....so I figured that I can just bend the trailing edge up (towards the front of the sky) and put a 83mm ring and see if I can hit 8550 rpm again, but after looking at the prop it appears as if it was as far forward as it could go....

    Anybody have any input on this?

    Could my prop be bent too far forward to be robing rpm's now?

    I did install the stock impeller back on with a 83mm and hit 8600 rpm's no problem...top speed 75mph.


  2. #2
    That is a lot of prop. I have just over 300 hp and am currently running a 3-blade 15/19.75 @ 8550 with the 82 mm ring.

    Mark

  3. #3
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    I would agree, to much prop.. I run about 300HP myself with a 15/18.5 SKAT swirl 3 blade in the Florida heat @ 8550 RPM.

    Alex

  4. #4
    BlackHawk's Avatar
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    I really don't get it then...I was running it before when it was 15/19 and I was hitting my rev limiter.....then I sent it off to pitch it so I'm at 8500 rpm's.

  5. #5
    BlackHawk's Avatar
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    I'm starting to think that skat trak pitched it wrong.

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    Quote Originally Posted by BlackHawk View Post
    I really don't get it then...I was running it before when it was 15/19 and I was hitting my rev limiter.....then I sent it off to pitch it so I'm at 8500 rpm's.
    Are you running a stage III or equ.? if so, they pitched it wrong.. When I pitched down 1/2 of a degree, I gained 200 RPM's. So, if you where at 8?00 with the stock 15/19 and pitched to a 15/19.5 you should have lost 200 RPM's. Sounds like you either got damaged during transit or you got pitched wrong..

  7. #7
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    Quote Originally Posted by Alex13 View Post
    Are you running a stage III or equ.? if so, they pitched it wrong.. When I pitched down 1/2 of a degree, I gained 200 RPM's. So, if you where at 8?00 with the stock 15/19 and pitched to a 15/19.5 you should have lost 200 RPM's. Sounds like you either got damaged during transit or you got pitched wrong..
    Yeah it looks like they might got the pitch wrong...I'm sending it back to check....is there a quick way I can check the pitch?

  8. #8
    If it's a 15/19.5 there should be approx. 11/32" table to blade tip.

    Mark

  9. #9
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    Quote Originally Posted by Mark S View Post
    If it's a 15/19.5 there should be approx. 11/32" table to blade tip.

    Mark
    Is that the tip of the trailing edge?

  10. #10
    Yes, tip of the trailing edge.

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