[Varrattu]

Basically, the iL2COD-DB601A follows a "running-line" of U/min and ATA:

1 min. erhöhte Kurzleistung.........1,45 ata - 2600 U/min -- start / emergency
5 min. Kurzleistung....................1,35 ata - 2400 U/min -- climb and combat
höchstzulässige Dauerleistung.....1,30 ata - 2200 U/min -- max. continuous
wirtschaftlichste Dauerleistung....1,10 ata - 2200 U/min -- economic cruise

Of course it is possible to use intermediate settings. The power remains fairly steady during the climb but above the critical altitude (4,5 km for the DB601A-1) further increases in altitude will cause the manifold pressure to decrease because the supercharger has reached its performance limit.

Try lowering the pitch so RPM are around 2100-2300 and manifold pressure around 1.3 ata. You'll constantly have to adjust the pitch in order to maintain RPM while velocity increases. It feels a bit like accelerating in a car using a high gear. In fact its nothing else.

Long story short, you will need to fiddle with the pitch control all day long. Don't expect to set it around 2200 as an all-around happy medium, leave it there and attain top performance.

~S~ Varrattu