PR------Air Flow----RWHP Tgt------Stock HP
1.53------0.35----------400------------------300
1.73------0.38----------450
1.92------0.43----------500
2.01------0.44----------525
2.11------0.46----------550
2.20------0.48----------575
I don't do math, Excel is my friend.
This is using the Rotrex install information.
There are many other factors but it is a start
Use the compressor maps and find the intersection of the lines, that is the speed you have to spin the unit.
There is heat energy loss (that is % in the compressor map), intercooler pressure drop, intercooler temp drop