Ok, George et all and the stickies are starting to penetrate. Now, you need to get deeper into the way the PCM thinks. Specifically, it thinks of fueling in terms of EQ or Equivalence Ratio, whereas our human hot rod brains are classicly in trained to comprehend AFR values, ie. ~13 to 1 at WOT making max power. Well the key to understanding it is that it is a Ratio, that is not linear but logrythmic and therefore with all the modifiers in the soup the PCM can't digest the final Commanded fueling in "Air Fuel Ratio." The math doesn't pan out in AFR but it does in EQ Ratio. The attached files are just a start, you can sit down with a calculator and make as fine as a truth table as you want or if you are real whiz just figure it out in your head. Some like a calculator, I prefer a short list for quick reference. The other attached file is Lambda vs. AFR. For scaling the MAF, I set up a calculation based on Lambda which by the way is a inverted ratio compared to EQ, thus, in EQ higher numbers are richer, and in Lambda, leaner. I find Lambda correction for the MAF simpler going in 1% corrections up or down. I guess in this case you could go with "what feels good."