I have spent hours trying to zoom into small sections of the log file then exporting to a CSV, then going through excel and making a query import. By the time you deal with Excel and text to number conversion and all these other stupid things you've spent 4 hours trying to compare airmass from a "before" run where you say had a stock piece on, and a "after" run where you put a ported piece or some aftermarket bolt on or something. We also have the added problem that we need a common RPM or other value to gauge from, which requires making up a pseudo new RPM, then pulling data points from both before and after run files that most closely match this new pseudo RPM you created. This way you can graph say airmass (which basically models torque and should be proportional to it) from both runs all on one x-axis of psuedo RPM. I've been doing this using VLOOKUP with an "approximate" match, but who knows how Excel is internally choosing which vlookup it choses.
Anyone else doing anything like this? I feel like the accuracy is there given modern MAFs and systems, and I would personally trust it way more than some "tuners" dyno who applies who knows what kind of corrections and tricks to make it look like their parts increased airflow and made more power.