Direct replacement Bypass valve for eaton superchargers such as the VMP 2.3L TVS for Cobra, GT500, and 5.0L. Fits Roush superchargers. Also fits stock M122 and M112 superchargers found on GT500 and Cobra. Fits VMP Gen3 and Gen3R for GT500 and coyote. Fits Odin supercharger. When installed top port must be referenced to vacuum after the throttle body or vacuum and boost. The bottom port may be referenced to the CAI before the throttle body or left open to atmosphere. If your BPV stays open and you drop boost it should be refenced to a source that sees boost and vacuum such as the line going to the fuel rail pressure sensor.