FixVault

Ignition Timing

NOTE: Some engines may include a magnetic timing probe socket. Insert probe into timing socket until it almost contacts vibration damper. Socket is located 9.5° ATDC. Do not use the probe location to check timing using a conventional timing light.
  1. On 1975-77 models, warm engine to operating temperature and ensure air cleaner is installed. Set timing with engine at idle speed and distributor vacuum hose disconnected and plugged.
  2. On 1978-79 models, ignition timing procedures will vary with vehicle model and component application. Refer to Emission Control Tune-Up Decal in engine compartment for correct adjustment procedures.
IGNITION TIMING SPECIFICATIONS (DEGREES BTDC@RPM)

Application Timing
1975-76
  260"
    Federal 18°@1100
    Calif. 14°@1100
  All Others 12°@600
1977
  301" 12°@550
  305" & 350" (VIN "L") (1) 8°@500
  350" (VIN "R") (2) 20°@1100
  350" (VIN "H" & "J") 12°@600
  403"
    Federal 24°@1100
    Calif. & High Alt 20°@1100
1978
  301" 12°@1100
  305" Federal 4°@500
  305" Calif. 6°@500
  305" High Alt 8°@500
  350" (VIN "L") (1) 8°@500
  350" (VIN "R") 20°@1100
  350" (VIN "X") 15°@600
  403" 20°@1100
1979
  301" 12°@650
  305" 2-Bbl. 4°@600
  305" 4-Bbl.
    High Alt 8°@600
  All Others 4°@500
  350" (VIN "L") 8°@500
  350" (VIN "R") 20°@1100
  350" (VIN "X") 15°@550
  403" 20°@1100
(1) Set High Alt. models at 600 RPM.
(2) Set Skyhawk, LeSabre and Estate Wagon to 18°@1100.