If you don't have any other airflow mods, your stock injectors can handle 9psi. You will need a bigger fuel pump and a powerdyne speed density calibration kit 65$ approx. You can also make a check valve system( similar to the powerdyne kit) I use to have a supercharged speed density mustang that have been stolen 2 years ago
. E-mail me if you some details on that check valve system. My car was running like any other mass-air car.