The LS6 VCT mod is more of a cleaning up the engine then giving it an improved performance. The LS6 VCT like Cutlas stated moves the PCV to underneath the VCT and away from the valve covers where oil flow is at its highest chance of getting sucked into the PCV. Only will a catch can filter he oil from the vapor. And IMHO it's a cheaper mod for $58 to do then replacing the PCV hose for $130.