Cylinder Head Assembly: Specifications

Cylinder head and valve train
Cylinder head gasket surface flatness 0.05 mm (0.002 inch) per 51 mm (2 inch) 0.10 mm (0.004 inch) per total surface area
Cylinder head thickness - minimum 95 mm (3.74 inch)
Valve guide bore diameter 7.003-7.029 mm (0.276-0.277 inch)
Valve stem diameter 6.947-6.965 mm (0.2735-0.272 inch)
Valve stem-to-guide clearance 0.140 mm (0.0055 inch) maximum
Valve head diameter
Valve face runout (T.I.R. max) 0.038 mm (0.015 inch)
Valve face angle
Exhaust 37.5 degrees
Intake 30 degrees
Valve seat width
Exhaust 1.80-2.56 mm (0.071-0.101 inch)
Intake 1.48-2.24 mm (0.058-0.088 inch)
Valve seat runout 0.0035 mm (0.0014 inch)
Valve seat angle
Exhaust 37.5 degrees
Intake 30 degrees
Valve spring free length 51.96 mm (2.045 inch)
Valve spring solid height 36.1 mm (1.42 inch)
Valve spring compression pressure 46.30 mm @ 340 +/- 17 N (1.82 in 76.5 +/- 3.8 ft. lbs.)
Valve spring compression pressure 383 mm (15.07 inch) @ 858 43 N (1.51 in @ 191 9.7 lbs)
Camshaft
Gear backlash 0.179-0.315 mm (0.007-0.012 inch)
Lobe lift
Intake 5.744 mm (0.2261 inch)
Exhaust 5.832 mm (0.2296 inch)
Allowable lobe lift loss 0.51 mm (0.02 inch)
Journal diameter 61.987-62.013 mm (2.440-2.441 inch)
Camshaft journal bearing inside diameter 62.05-62.14 mm (2.443-2.446 inch)
Camshaft journal-to-bearing clearance 0.037-0.153 mm (0.0015-0.0060 inch)
End play 0.051-0.211 mm (0.002-0.008 inch)
Exhaust manifold warpage maximum allowable clearance (cold) 0.0762 mm (0.003 inch)
Intake manifold warpage between ports 0.13 mm (0.005 inch)
Intake manifold warpage - total 0.25 mm (0.0010 inch)
Head gasket surface flatness 0.10 mm (0.004 inch) across the total area 0.05 mm (0.002 inch) across any 150 mm (5.9 inch) x 150 mm (5.9 inch) area 0.025 mm (0.001 inch) across any 25 mm (0.98 inch) x 25 mm (0.98 inch) area

Cylinder Head

New Head Bolts Must Be Used

Install the cylinder head retaining bolts finger-tight.
Tighten the head bolts in the following sequence.
1 Tighten bolts 1 through 10 to 88 Nm (65 ft. lbs.).
2 Tighten bolts 1, 3, 5, 7 and 9 to 115 Nm (85 ft. lbs.).
3 Tighten bolts in sequence 1 through 10, clockwise 90°.
4 Tighten bolts in sequence 1 through 10, a second time, clockwise 90°.
5 Tighten bolts in sequence 1 through 10, a third time, clockwise 90°.
6 Tighten bolts 11 through 15 to 24 Nm (18 ft. lbs.).
7 Tighten bolts 11 through 15 to 31 Nm (23 ft. lbs.).

Exhaust Manifold LH
Install the LH manifold and bolts.
Tighten in the sequence shown.
Tighten all bolts to 38 Nm (28 ft. lbs.).

Exhaust Manifold RH
Install the RH manifold and bolts.
Tighten in the sequence shown.
Tighten all bolts to 38 Nm (28 ft. lbs.)

Coolant pump 23 Nm (17 ft. lbs.)

Late build

Intake Manifold
Install the intake manifold and bolts and tighten in the following sequence.
In the sequence shown.
1 Loosely install bolts 1-8.
2 Tighten bolts 9-16 to 11 Nm (8 ft. lbs.).
3 Tighten all bolts to 11 Nm (8 ft. lbs.).

Early build