Atmospheric BOV`s might help more air to pass, but, having an Air Flow meter equipped car you confuse the ECU and undo any bennifits you could achieve.
I would recommend using a GREDDY plum back style, Which flows 2-3 times the air. It might not sound as good as the standard , but, the truth of the matter is the more restrictive your BOV is the louder it is.
Or you can get away with an atmospheric type when using a S-AFC as this is equipped with a function that momentarily sends a preset A/F meter signal to the ECU when the BOV is venting. No more kneecapping flames !
Agreements - Disagreements ?