Here is what I log:
RPM, Engine load, Mass Air Flow, Intake Air Temp, Ignition Angle, Injector time, Oxygen sensing, banks 1&2 Lambda Value, Boost pressure of sensor, Setpoint boost, Boost pressure control P/D factor, Correction factor for BPC with knock control

Engine load in % seems to be a pretty good proxy for volumetric efficiency and for torque. Not quantitative, but a good relative measure. My car peaks around 205%. The guys with bigger turbos and fueling mods see 235,240, maybe more. I don't know what the really big power guys see.

Air temps will tell you how well your intercoolers are doing. Once you start to see 60 deg C, you're losing a lot of power

Ignition angle will let you know when timing is being retarded

Injector time tells you about how your fueling is keeping up. I like to see it as duty cycle, computed in % as (injector time)*(RPM)/1200. You don't want to see numbers over 100%. You're underfueled, and risk detonation.

O2 sensor lambda values give you air:fuel ratio (multiply by 14.7). At idle, you should see 1. Under boost, numbers from 0.7-0.85, depending on the tune. Track tunes tend to run lower numbers (richer) than street tunes, from what I have seen.

Boost pressures are reported in mm Hg absolute. Get boost reading of your gauge as (Pressure - Pressure @ idle)/760

Correction factor for knock - mine is always 1. I've been told that if I see values of 0.97 I should park the car until it gets diagnosed

Hope that helps.

Jon

 

thumbs up, someone sticky this with a topic "how to log" because this is quite useful.

Cheers

 

Guys can you tell me, does Durametric version 6 have the issue where fault codes have to have the digits flipped to get the ACTUAL fault you are having??