Originally Posted by jimmyblue

Once you have better visibility into the coming and going
of KR, you can back into the causes; you can look at the
changes (up-KR) and see what precedes them. Look in
particular for hard dips in the O2 voltage on opening
throttle, which show a lean transient; there are "holes"
in the stock setup, where you fall out of the combined
MAF/SD normal airflow metering mode and into straight
speed density; speed density error is changed by any
mods aft of the intake manifold, and any mod worth
doing biases the error toward the lean side. Change in
MAP, like from opening throttle, is the trigger here.
If your O2s jack lean for a while after you mash it, you
know you have to fix the VE table. If the dip is very
brief then maybe you want to play with transient fueling
or just patch it over with burst knock retard, but more
than a couple "ticks" worth of lean dip is saying VE is off,
in the MAP*RPM region you just left.