Well... they work just fine with a BOV... its just when idiots set the spring to low and it goes off in neutral or at too low a rev and removes the air the MAFS has already read from the system, so the computer has already read air that gets vented, and runs rich for a second.... You set your BOV and you are all good, there is also kits, or just BOV's that recerculate that air back into the system (before the mafs) to prevent some of this problem. Bovs are for when you get off the gas, shift, etc to remove the extra uneeded pressure in the intake system (don't remove boost or adjust boost) there is no trouble with running atmospheric BOV's its just when they are set wrong that they don't work.