MX-5 Miata Mazdaspeed L4-1.8L DOHC Turbo (2004)
Valve: Testing and Inspection
Valve Inspection
1. Measure the valve head margin thickness of each valve. Replace the valve as necessary.
2. Measure the length of each valve. Replace the valve as necessary.
Standard length
IN: 101.71 - 102.31 mm (4.0044 - 4.0279 inch)
EX: 101.71 - 102.31 mm (4.0044 - 4.0279 inch)
Minimum length
IN: 101.61 mm (4.0004 inch)
EX: 101.61 mm (4.0004 inch)
3. Measure the stem diameter of each valve in X and Y directions at the three points (A, B. and C). Replace the valves as necessary.
Standard diameter
IN: 5.970 - 5.985 mm (0.2351 - 0.2356 inch)
EX: 5.965 - 5.980 mm (0.2349 - 0.2354 inch)
Minimum diameter
IN: 5.920 mm (0.2331 inch)
EX: 5.915 mm (0.2329 inch)