Cam phasers are specially designed, computer-controlled cam gears that automatically optimize camshaft timing based on the current engine rpm. Currently they are used in all 2005 and newer Ford Modular 3 Valve and all 2007 and newer GM L92 engines. Engine oil is pressure fed to the cam phasers through a series of passageways in the cylinder heads and camshafts. The engine computers control solenoids that adjust this oil flow into and out of the phaser's control chambers, giving the ability to retard the cams up to 60 crank degrees.
This limiter kit for '11-'14 Ford 5.0L Coyote limits the cam phasing to 25 crank degrees for camshafts with more duration and lift. By keeping VVT while adding larger camshafts, more power is gained without sacrificing bottom end torque.
For Ford 5.0L Coyote applications; Automatically optimize camshaft timing based on the current engine rpm; Computer controls the oil flow in and out of the phaser's chambers giving the ability to retard the cam up to 60 degrees

Fitment:
Ford Mustang GT 2011