Each piston face has a dished surface, to preload the valve shims flat against the piston face. The standard dishing is 1° on both the compression and rebound sides of the piston. By increasing the compression side dishing to 2°, the shims become increasingly preloaded, causing a slight delay in opening during compression movement. The dishing causes the shims to "snap" open, in return giving the car a "snappier" feel as opposed to a smooth roll, once again this modification is for driver feel. If you have questions on piston dishing, call our technical staff for information and recommendations.