I would like to thank Tomo, Snowygrouch and Algernon for their help with the data that I am looking for. Unfortunately, I still haven't found all the data that I need but I am happy to say that I have made considerable progress toward that goal, thanks to the above-mentioned people.
During my research on some of the performance aspects of the Jumo 211A and 211B engines, I came across a number of problems that I need to solve in order to complete my calculations. The power curves of the Jumo 211A and Jumo 211B that I have found so far are these:
Jumo 211A:
http://www.muzeumlotnictwa.pl/digitalizacja_archiwaliow/katalog/2285/18.jpg
Jumo 211B to Jumo 211H:
https://ww2aircraft.net/forum/attachments/jumo-211-b-h-power-curves-pdf.65468/
These documents are very informative. However, I also need the following data on the Jumo 211A and/or Jumo 211B:
1. Air-fuel ratio
It may take the form of mass parts of air to mass parts of fuel (for example, 12.5:1, which would be a rather rich mixture), or
λ (lambda) which is derived from the actual air-fuel ratio divided by the stoichiometric air-fuel ratio (which is when exactly enough air is provided to burn all the fuel, 14.7:1 in the case of gasoline). So, a rich mixture would have
λ less than 1, and a lean mixture would have
λ more than 1.
2. Brake Mean Effective Pressure Differential (BMEPd)
To clarify, the Brake Mean Effective Pressure Differential (BMEPd) is different from the Brake Mean Effective Pressure (BMEP). BMEP can be easily calculated given the Power (for example, from the Power Curves) and the Theoretical Volumetric Flow Rate (derived from engine displacement and RPM). However, the BMEPd is derived from the Measured (i.e., actual, not theoretical) Volumetric Flow Rate, and therefore is different from BMEP. Both are measured in units for pressure.
3. Volumetric efficiency (VE)
This is the ratio between the Measured Volumentric Flow Rate and the Theoretical Volumetric Flow Rate. The ratio is of course dimensionless, but the Flow Rate is measured in cubic feet per minute or cubic meters per second.
Any help will be highly appreciated.