DESCRIPTION: Dual outlet-type BOV. Dual Port vents both to the atmosphere and back into the air intake. Ports with sequential timing allow quieter operation during normal driving, while getting all the benefits of a vent-to-atmosphere BOV under race conditions. Easily converted to a full atmospheric or full bypass unit by using supplied port blanking plug.
I'm assuming this means driving around soft at a low Psi it only moves the piston enough to vent through the plumb back, but when you hook it and the boost climbs the piston moves further allowing the air to escape through both ports.
