Valve Spring
WARNING: This page is about a different car, the 2022 Subaru WRX. However, it is still accessible from the selected car via links, so may be relevant.
- Check the valve spring for damage and deformation.
- Using a caliper gauge and valve spring tester, check the valve spring free length (reference) and tension/spring height. If it is not within the standard, replace the valve spring.NOTE:
- Measurement should be performed at a temperature of 20°C (68°F).
- Valve spring free length is described as a reference. If only valve spring free length is out of the standard, it is not necessary to replace the valve spring.
Valve spring free length (reference):
Standard
43.28 mm (1.7039 in)
Valve spring tension/spring height:
Set
Standard
182 - 210 N (18.56 - 21.41 kgf, 40.92 - 47.22 lbf)/34.50 mm (1.3583 in)
Lift
Standard
483 - 533 N (49.25 - 54.35 kgf, 108.60 - 119.84 lbf)/24.80 mm (0.9764 in)
- Using thickness gauge, surface plate and try square, check the squareness of the valve spring. If it is not within the standard, replace the valve spring.NOTE:
Measurement should be performed at a temperature of 20°C (68°F).
- Place the valve spring on the surface plate, with smaller diameter end facing up.
- Using try square and thickness gauge, measure the clearance at the point of 30 mm (1.1811 in) from the bottom, between one coil and the square.
Valve spring squareness (at height of 30 mm (1.1811 in)):
Standard
2.5°, 1.4 mm (0.0551 in) or less