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A few comments on racing:

Based on trial and error with my Pitts with 76" diameter Sensenich prop I found the best pitch was 60" which allowed a maximum? r'/m of 3300 at 200 statute indicated. I think this translates somewhat to racing the Tailwind with a fixed pitch. I flew cross country with the Pitts as high as 2900 r/m. I am told that is what Steve used for the racers with a cross country prop and a separate prop for racing.

I think 2900 would be the optimum for the Tailwind for the SARL racing.?

having said that I recorded some numbers yesterday with the Whirlwind GA on my W10. 0 320 with 10-1 compression. The engine is balanced, no other mods.I respect the 2700 r/m limit for the Whirlwind prop.?

My cowl flap is stuck in the half open position. Aft portion of wheel pants removed because of rough runway.

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For reference temperature used for true airspeed was from Winds aloft forecast. Altitude was pressure altitude. Temperature at 3000' was 23C which is 14c above standard altitude

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3000' 24" and 2550 r/m

185 statute indicated

175 knots true airspeed

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6000' 22' 2650 r/m

190 statute indicated airspeed

183 kt? True airspeed.?

The cowl flap and wheel pants are probably a 5 knot reduction in speed.?

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I have previously seen True airspeeds as high as 190 at altitudes around 10,000'

I claim? 170 kts/195 statute cruise.?

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I am happy with the Whirlwind prop and don't plan to change props. I do believe a prop that would turn 2900 r/m full throttle would be significantly faster for racing.?

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