no 2 setup are 100% the same, don’t forget. engine condition, heat, wear exhaust ect etc, everything matters. Even 2 identical cars 1 may be something slightly diffrent causing different outcomes.
As said
"if it is the same car with the same turbo and you change the boost from 15psi to 20psi (using a wastegates set at those 2 pressures) then there will be no power difference until the boost goes above 15psi when you have the boost wound up. from the moment the second setup goes above 15psi the power and torque will change. below that the will be 100% the same. if it is 2 different turbos then it comes down the compressor properties."
is all there is to it, and don’t forget dynos aren’t 100% accurate and are effected my environmental conditions. Just like cars are with heatsoak
..a dirty air filter can be a factor .. if you get what im saying.