your SS isnt boosted nor does it run the same type of ecu parameters. and btw… tuned subarus generally run 10.8:1 to 11.5:1 AFR under boost. even if it does lean out slightly you are still 12.2-12.5:1 under full boost which is still “rich” for most of you NA boys, and well within a “safe” zone to operate the vehicle without any problems.