I don't know. Idle AFR is around 12.5:1. Low load is around 14.0-14.7:1. I noticed that thay are kind of high too but that's what seems to make the car run best.
2016 WRX STi Limited (current)2001 A4 1.8tqms (donated)1991 GVR4 #1933 (sold)old.dsmregistry.com/detail.php?carid=218 (dismantled)