Thank you for all your advice.
As a reminder, the question was not whether one can pull more power than allowed by the limit chart.
But rather whether it is to be expected that one can pull more inches Hg MAP over and above the value that the manufacturer says one cannot exceed because the throttle is already fully open. And whether observing such higher indicated MAP value would suggest either a faulty MAP gauge or a leak in the vacuum line to the MAP gauge.
Maybe this picture from the Internet can help. In this example:
- MCP is limited 22.7 inHg
- Take-off Power should be 24.3 inHg
- However, at 23.3 inHg the throttle is already fully open, and the book suggests that you cannot pull higher MAP
If one pulled more collective, MAP is supposed to stay at that full throttle value, but RRPM droops due to higher angle of attack/drag.
Some of us however report here that this is not necessarily the case.