GMC 1990 Light Truck Repair Manual page 439

All specifications are in MILLIMETERS unless otherwise noted.
CRANKSHAFT
Diameter - 3 Dots
Diameter - 2 Dots
Main Diameter - 1 Dot
Journal Taper
Out of Round
Main Bearing Clearance
Crankshaft End Play
Diameter — 2 Dots
Diameter — 1 Dot
Crankpin
Taper
Out of Round
Rod Bearing Clearance
Rod Side Clearance
CAMSHAFT:
Lift
Journal Diameter
Journal Clearance
VALVE SYSTEM:
Lifter
Rocker Arm Ratio
Intake
Valve Lash
Exhaust
Face Angle (Intake & Exhaust)
Seat Angle (Intake & Exhaust)
Seat Runout (Intake & Exhaust)
Intake
Seat Width
Exhaust
Stem Clearance
Free Length
Valve Pressure
Spring N @ mm
Installed height
Valve Spring Free Length
Damper
Approx. # of Coils
SPECIFICATIONS
ENGINE SPECIFICATIONS (CONT.)
Intake
Exhaust
Closed
Open
2.8 LITER V-6 6A2-29
67.241-67.249
67.249-67.257
67.257-67.265
0.005 (Maximum)
0.005 (Maximum)
0.041-0.081
0.06-0.21
50.758-50.771
50.771-50.784
0.005 (Maximum)
0.005 (Maximum)
0.035-0.095
0.16-0.64
6.65
6.94
47.44-47.49
0.026-0.101
Hydraulic
1.50:1
One And One Half Turns
Down From Zero Lash
45°
46°
0.05
1.25-1.50
1.60-1.90
0.026-0.068
48.5
391 @ 40
867 @ 30
40
47.2
4
F-05525