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Old 04 July 2016, 04:16   #11
Country: USA
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Originally Posted by Pikey Dave View Post
Are you sure about that? Normally you gain rpm when changing from ally to stainless for the same pitch.
Backwards. SS is stiffer, so it holds pitch under load. Aluminum sheds a bit under load, so revs higher. In addition, SS props usually have more cup, and weigh more, both of which lower rpm even more.


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Old 04 July 2016, 07:50   #12
Country: UK - England
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is is actually a 90 as its not just swapping the carbs.. my SR 54 ran 13x19 and would gain just touching 40 at 5300..(documented figures at the time)

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Old 04 July 2016, 08:43   #13
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400-500rpm would be a lot on a like for like. I've found very little change in rpm and maybe a couple of MPH improvement at the top end. The blades don't flex as much but they're thinner and present less rotational resistance.

I did find the slip from a vented Laser 11 let me push the pitch a bit further without compromising hole shot. (compared with the Vengence I took off).

40mph+ with a 15" would have to have a unusual gear ratio at 5500.

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