Piston Ring, Engine

Piston ring end gap - top and bottom 0.23 - 0.49 mm (0.01 - 0.02 inch)
Piston ring end gap - oil ring (steel rail) 0.05 - 0.66 mm (0.006 - 0.026 inch)
Piston ring groove width - compression (top) 1.520 - 1.550 (0.06 - 0.610 inch)
Piston ring groove width - compression (bottom) 1.520 - 1.530 mm (0.060 - 0.0602 inch)
Piston ring groove width - oil ring 6.996 - 7.224 mm (0.275 - 0.2844 inch)
Piston ring width - compression 1.49 - 1.47 mm (0.0587 - 0.0579 inch)
Piston ring width - oil ring rail (2) 0.473 - 0.447 mm (0.0186 - 0.0176 inch), 0.483 mm (0.0190 inch) maximum at ID
Piston ring width - oil ring expander 2.038 - 1.960 mm (0.080 - 0.077 inch)
Piston ring - to - groove clearance - compression 0.030 - 0.070 mm (0.0012 - 0.0028 inch)
Piston ring - to - groove clearance - oil ring assembly 0.046 - 0.196 mm (0.0018 - 0.0077 inch)