MX-5 Miata Mazdaspeed 18L Turbo Piston Ring Specifications
Piston Ring: Testing and Inspection
Piston Ring Clearance Inspection
1. Measure the piston ring-to-ring land clearance around the entire circumference. Replace the piston and piston ring as necessary.
Standard clearance
Top: 0.030 - 0.065 mm (0.0012 - 0.0025 inch)
Second: 0.030 - 0.070 mm (0.0012 - 0.0027 inch)
Oil: 0.07 - 0.18 mm (0.003 - 0.006 inch)
Maximum clearance
Top, Second: 0.15 mm (0.006 inch)
Oil: 0.20 mm (0.008 inch)
2. Insert the piston ring into the cylinder by hand and use the piston to push it to the bottom of the ring travel.
3. Measure each piston ring end gap by using a feeler gauge. Replace the piston ring as necessary.