yes, you have to have the predator hooked up in order to data log the car...
you need to do a steady drive/cruise on the highway (not WOT, hauling ass), keeping your rpms between 1800-2000....
and you need to select these parameters to record/log:
Air Fuel Ratio (Equivalence Ratio) = Under FUEL menu
Long Term fuel trim bank 1 = under FUEL menu
Long Term Fuel Trim Bank 2 = under FUEL menu
Spark Advance = under IGNITION menu
Intake air Temp = under INTAKE menu
MAF Sensor Mass Air Flow = under INTAKE menu
Total Knock Spark Retard = under MISFIRE menu
Engine Speed (RPM) = under PERFORMANCE menu
Commanded Throttle position = under THROTTLE menu
here's some info about data logging: