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Date: Wed, 30 May 2012 10:55:27 -0400
From: Ernest Christley <echristley@att.net>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Exhaust temp
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Charlie England wrote:

> As someone else pointed out, it would pay to look at the prop first.
> What's the prop rpm? If it's anything close to typical a/c engine static
> rpm (2000-2300, depending on pitch), then you might be able to borrow a
> regular wood prop from someone to use as a benchmark. Knowing the design
> HP & static for a specific prop, & checking your performance against it,
> will give you a much better handle on how much power you're actually
> making.
> 


Excellent idea, Charlie.  A quick and easy test for me would be to put my test club back on and see what it does now
that I have the engine tuned better than "it'll run".  I have a 3.14:1 reduction, which only puts the prop in the
1600rpm range at full throttle.  That's slow, but we've talked before how my first attempt at designing a prop has an
extreme amount of pitch.

I do want to open up that down pipe.  Going to 2.5" pipe will triple the cross section.  But, for now I'll check that I
can get above 5100 with the test club, and then see what the acceleration is like when I move to the airport and start
taxi testing on the 16th.