compressor map question
 

I am sorting out which turbo I'm going to use and I am looking at the compressor map for the s363. I know about how many lbs/min I want to be at, but how do I know where to plot pressure ratio? How much will the plot change based on turbine aspect ratio, or does that not relate? Is there a rule of thumb on efficiency percentage not to drop under for pump gas cars with no water/meth?

Will a Mod move this to the single turbo category? I fat fingered it.

FC3S Pro v2.0:&nbsp Turbo Tech - Compressor Maps

the pressure ratio is how much boost you want to run starting from a complete vacuum
1 = 0 psi
2 = 14.7 psi
3 = 29.4 psi

turbine doesn't affect the compressor map because it's unrelated to how efficient the compressor side is.