Cylinder Head, Valve Guides and Valve Seats
CYLINDER HEADValve Seat Run - Out (Maximum) 0.760 mm (0.003 in.)
Intake Valve Seat Angle 45 - 45 1/2°
Seat Width (Finished) 1.75 - 2.25 mm (0.069 - 0.088 in.)
Exhaust Valve Seat Angle 45 - 45 1/2°
Seat Width (Finished) 1.50 - 2.00 mm (0.057 - 0.078 in.)
Cylinder Head Gasket (Thickness Compressed) 1.78 mm (0.070 in.)
VALVE GUIDES
Type Powdered Metal Inserts
Guide Bore Diameter 7.975 - 8.000 mm (0.314 - 0.315 in.)
VALVES - (INTAKE)
Head Diameter 45.5 mm (1.79 in.)
Length Overall (New) 125.385 - 126.025 mm (4.936 - 4.961 in.)
Stem Diameter (Standard) 7.935 - 7.953 mm (0.312 - 0.313 in.)
Stem to Guide Clearance 0.025 - 0.095 mm (0.001 - 0.003 in.)
Maximum Allowable (By Rocking Method) 0.247 mm (0.010 in.)
Face Angle 44 1/2°
Valves for Service Std.
0.015 mm (0.005 in.)
0.40 mm (0.015 in.)
0.80 mm (0.030 in.)
Lift (Zero Lash) 10.16 mm (0.400 in.)
Minimum Valve Length After Grinding Tip 124.892 (4.916 in.)
Valve Tip Height,
From Head Surface 49.541 - 51.271 mm (1.95 - 2.018 in.)
VALVES (EXHAUST)
Head Diameter 37.5 mm (1.476 in.)
Length Overall (New) 126.095 - 126.645 mm (4.964 - 4.986 in.)
Stem Diameter (Standard) 7.906 - 7.924 mm (0.3112 - 0.3119 in.)
Stem to Guide Clearance 0.051 - 0.175 mm (0.002 - 0.006 in.)
Maximum Allowable by Rocking Method 0.414 mm (0.016 in.)
Face Angle 45°
Valves for Service Std.
0.015 mm (0.005 in.)
0.40mm (0.015 in.)
0.80 mm (0.030 in.)
Lift (Zero Lash) 10.16 mm (0.400 in.)
Minimum Valve Length After Grinding Tip 125.512 mm (4.941 in.)
Valve Tip Height
From Head Surface 49.541 - 51.271 mm (1.95 - 2.018 in.)
VALVE SPRINGS
Number 12
Free Length (Approx.) 48.5 mm (1.909 in.)
Wire Diameter 4.75 mm (0.187 in.)
Number of coils 6.8
Load When Compressed,
Valve Closed 95 - 100 lbs. @ 1.570 in.
Valve Open 207 - 229 lbs. @ 1.169 in.
Valve Spring Installed Height
Spring Seat to Retainer 41.2 - 42.7 mm (1.622 - 1.681 in.)