I know that the usdm obd2 ecu's detune the vafc settings after a week or so. I'm curious if jdm ecu's do too. A jdm p73 doesnt look for a 2nd O2, right? So, then it wouldnt be as anally retentive about emissions. Any help would be great.

cliff notes: do vafc settings actually makes a difference for longer than a week when used w/ a jdm obd2 ecu????