Piston Ring, Engine

Piston Rings (End Gap Measured in Cylinder Bore)
Piston Compression Ring Gap (Production-Top Groove) 0.25 - 0.40 mm (0.098 - 0.015 inch)
Piston Compression Ring Gap (Production-2nd Groove) 0.46 - 0.66 mm (0.018 - 0.025 inch)
Piston Compression Ring Gap (Service-Top Groove) 0.25 - 0.50 mm (0.009 - 0.019 inch)
Piston Compression Ring Gap (Service-2nd Groove) 0.46 - 0.80 mm (0.018 - 0.031 inch)
Piston Compression Ring Groove Clearance (Production-Top Groove) 0.030 - 0.070 mm (0.0012 - 0.0027 inch )
Piston Compression Ring Groove Clearance (Production-2nd Groove) 0.040 - 0.080 mm (0.0015 - 0.003 inch )
Piston Compression Ring Groove Clearance (Service Limit-Top Groove) 0.030 - 0.090 mm (0.0012 - 0.0035 inch )
Piston Compression Ring Groove Clearance (Service Limit-2nd Groove) 0.040 - 0.100 mm (0.0015 - 0.0040 inch )
Piston Oil Ring Gap (Production) 0.25 - 0.76 mm (0.009 - 0.029 inch)
Piston Oil Ring Gap (Service) 0.25 - 0.90 mm (0.009 - 0.035 inch)
Piston Oil Ring Groove Clearance (Production) 0.046 - 0.096 mm (0.0018 - 0.0037 inch)
Piston Oil Ring Groove Clearance (Service) 0.046 - 0.100 mm (0.0018 - 0.0039 inch)