You asked about having an ap but to answer your question...no you won't need one. If you are gonna run with a bov, you may need to adjust it. Im not all that familiar with them because i run the stock bypass valve. But i do know that some will need adjusting. oh and you may check at the bov flange to make sure you have a good seal there. Sorry i don't have any more info. Hope you get it fixed man! Good luck.
Ps. are you getting boost? If so do you have a boost gauge? If so what boost are you hitting?
Cobb ap stage 2 ots, catless uppipe, catless turboback, Cobb Sf intake.