Piston Ring, Engine

Piston ring end gap - compression (top and bottom) 0.23-0.49 mm (0.010-0.020 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 mm (0.002-0.610 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)