Well now where do we start. Each turbo has its own effeciency "area". A T3 Super 60 will perform diffrently than a T3/T04b. There are diffrent trim levels which give an idea of where they effeciency of the turbo is. What you will need to look for is effeciency graphs for the turbos.
This is a effecinecy graph or map for a T3 Super 60 turbo. On the X axis or the lower axis is the amount of intake your car requires. There is a equation on how you get a number to see where you start at.
CFM = (L x RPM x VE x Pr)/5660
L= engine size in Liters
RPM= Rev per MIn
VE= Volumetric efficieny
Pr= Pressure Ratio.
VE is .90 or 90%
Pr= (14.7+boost)/14.7
You will need to figure out at least two points on the graph. One at idle where the PR =1 and one at redline so you can figure out what kind of effency you are getting out of the turbo. OR once you have the two points you can figure out the turbo that has the best effency for your application.