What is meant by….Trick ring face

Piston Ring Back Cut

This terminology is used to describe a compression ring with less than SAE standard D-Wall radial thickness. The radial thickness is defined as the ring’s inside diameter compared to the outside diameter. Back-cutting reduces natural radial ring tension by increasing the inside diameter. In applications where there is a tight top ring land-to-piston clearance problem, back cut rings allow them to be moved up toward the top of the piston, which improves combustion efficiency and provides more power.