Originally Posted by MaddMax
I love how everyone blames this initial lean condition at the on-set of boost yet no one has been able to confirm that it truely is the culprit.
It also has nothing to do with emissions. Ford manages to get their Focus ST (turbo) to run a 13:1 or less AFR at 3500rpms.
When I've logged my 2012 WRX with the Torque App, it shows an AFR at ~13.5:1 at the on-set of boost and the richening up into the 12s shorterly thereafter (~4200rpms).
That car can also run on 87oct and be "happy", it just lowers its power output. Subaru needs to step up their game.