You are welcome. Lag times and therefore the duration of your pinch will vary from engine type to engine type but that is soon corrected for with a little practice but then what is important is to always use the same duration each time.

I find this technique makes it possible and easy to choose operation closer to peak or a more conservative mixture and do it much more accurately than reaching peak then backing off some arbitrary RPM figure that may or may not even be whats needed for any particular engine and set of conditions (temperature, density altitude and humidity) .

John