Surface Piercing Propeller Slip
#11
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Mines a heavy slower boat but the slip is interesting. Running herring 4 blade 18x32x15 rake, Boat ran 85 at 5200rpm. Then I got some mercury 5 blade 18x35x18 rake, boat runs 77 at 4900 (haven't pushed it past that) it turns the bigger props easy, but they just slip like crazy. Tried all different trim settings. George at cool breeze at LOTO told me my boat might just "like the 4 blade props better".
Same slip to 5200 rpm gives 82mph. Not far off the 4 blade max speed.
Maybe the extra rake is giving it a hard time. You're turning in?
How is the cruising performance of the new props?
#12
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The 29% slip is with the mercury props. About 16% slip with the herrings. Yes props are turning in. As far as cruising, we ran it Sunday and I remember seeing around 50mph at 3100rpm. Which is like 39% slip. The rooster tail even looks lazy lol. I trimmed up and down, didn't help. Trimming up increased rpm but not speed. Kind of odd.
Sorry original poster, not trying to hijack your thread.