Piston Ring, Engine

Piston Ring End Gap
First Compression Ring - Production 0.3-0.45 mm (0.012-0.018 inch)
First Compression Ring - Service 0.45-0.675 mm (0.018-0.027 inch)
Second Compression Ring - Production 0.45-0.65 mm (0.017-0.025 inch)
Second Compression Ring - Service 0.675-0.975 mm (0.026-0.039 inch)
Oil Control Ring - Production 0.249-0.759 mm (0.0098-0.0299 inch)
Oil Control Ring - Service 0.373-1.138 mm (0.015-0.045 inch)

Piston Ring-to-Groove Clearance
First Compression Ring 0.031-0.074 mm (0.0012-0.0029 inch)
Second Compression Ring 0.031-0.074 mm (0.0012-0.0029 inch)
Oil Control Ring 0.051-0.203 mm (0.002-0.008 inch)