Yes you could.
But it may cause you problems. The WRX STI already has a blow off valve and it is plumbed the way it is for a reason. Once the air meter reads the air, it need to be kept in the intake loop (after the air meter and before the turbo). There are several reasons for it, like over rich problems, engines stalling prevention and spool up time reduction.
So do it it you want, it is just that the end result will be a poorer performer then what you started with.
Yes you could.
But it may cause you problems. The WRX STI already has a blow off valve and it is plumbed the way it is for a reason. Once the air meter reads the air, it need to be kept in the intake loop (after the air meter and before the turbo). There are several reasons for it, like over rich problems, engines stalling prevention and spool up time reduction.
So do it it you want, it is just that the end result will be a poorer performer then what you started with.