Paul kgyy writes:

The power chart in your POH should tell you how to adjust the manifold
pressure for nonstandard temperature conditions.

It says maximum cruise power at 20° rich of peak, 25" MP, 2500 RPM,
for minus 20 degrees OAT, with the best listed performance at 6000
feet (approximately 200 KTAS), although I'm at 5000 feet because I'm
IFR and that's not on the chart. That's about what I'm getting now
(211 KTAS with the same settings, as close as I can get them).
Economy cruise is about 40 kts slower, but I have virtual cash to
burn.

The cold air doesn't help performance, according to the POH chart.
Maybe it's the adjustments I'm making; I've only recently started
adjusting mixture and prop myself (I used to let the sim do it).

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