Reason of identical Result at the Dyno

Do I Understand correctly?

Is The same result at the summer and winter at the dyno achieved by settings at Standards conditions and when the conditions at the nature changed ECU make corrections +/- (quantity of fuel or turbo pressure) to archive same result?

Hello, Nikolay!

ECU continuously receives information from MAF/MAP and IAT sensors to calculate mass of air entering the engine and mass of fuel to inject for a target AFR/lambda. As density of air changes with altitude, humidity and temperature, the amount of available air will change for a same engine speed and throttle position. Consequently real horsepower and torque will also change.

Dynos, as far as I know, are equipped with sensors measuring ambient air temperature, pressure and humidity. This data is used to correct measured power and torque to produce same numbers at different conditions. Several standards for normal conditions have been developed.