when the egines are warmed up on the runway, you should disable the carb heating - activated it cost you some rpm (power)
i am actually disabling them short after the engines are running.
Having these temperatures in mind and not forgetting to correct the default set rudder trim the Blenheim is actually a nice plane to start with

Its a HotRod in comparison to the He111 as example
One have just to read the forums about that
as a rookie, one would never think about these two features i guess.
And not to forget the impossibility to change positions in the Blenheim online - because the temperatures are set to ZERO with each position switch ....................
I cant imagine how a person who is not active (at last reading) in a CoD forum is able to handle this software in its current state of development