compressor discharge pressure corrected

Dear all

in many papers, they introduce a correction factor for compressor discharge pressure correction called DELTA

DELTA = P ambient/P ref.
hence
cpd corrected = cpd/DELTA

this factor will have no effect if the ambient press is equal to or near the ref pressure.

my question is the inlet air temperature have no effect on the cpd. when i want to make a comparison between two values for the cpd to test the compressor performance

first state, inlet temp = 60 F, cdp =122.5 psi
second state, inlet temp = 64 F, cdp =118.5 psi
how to make the comparison, which state is better perf.

thanks in advance