Yep. When you go to WOT (wide open throttle - about 80% open) the engine goes into power enrichment and the commanded A/F goes to about 11.7-11.9 which is richer than for optimum power but conservative for GM warranties.

 

My fault:
A/F - air fuel ratio - 14.7:1 for best fuel economy and lowest emissions (stoich ratio) - about 12.5 - 13:1 for best power
MAF - mass air flow meter
g/s - grams per second
MAP - manifold absolute pressure - air pressure/vacuum in the intake manifold
VE table - volumetric efficiency table - give base air mass per cylinder values in a table of RPM versus MAP - used to determine air flow if MAF dies
Strim - short term fuel trim - moves quickly in response to precat O2 values to make part throttle A/F 14.7:1
Ltrim - long term fuel trim - moves slowly to bring the Strim to zero - the total fuel added or subtracted is the sum of the Strim and Ltrim (i.e., 5% + 6% = 11% fuel added - 11% longer injector pulse width)
WOT - wide open throttle - usually throttle >80% open - no A/F learning - Strim forced to zero
IAT - Inlet air temperature sensor - located inside MAF - electrically independent of MAF
ECT - engine coolant temperature sensor
Open loop - PCM adjusts A/f based on predetermiend values - usually when cold
Closed loop - PCM adjsuts A/F based on precat O2 to make A/F = 14.7:1