Valve Specifications

1983 Chevrolet Step Van P30, 4.8 T, Automatic, 400/M40SECTION Valve Specifications
VALVE SPECIFICATIONS

Application Inch (mm)
Face Angle 45Β°
Seat Angle 46Β°
Seat Width
Intake .031-.063 (.79-1.58)
Exhaust .063-.094 (1.58-2.38)
Stem Diameter .0010-.0027 (.025-.069)
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.