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Vacuum Advance

Alternately remove hoses (2) from distributor vacuum advance unit. Attach vacuum pump. Apply 15-17 in. Hg while observing base plate. Base plate should operate with a smooth movement and gauge indicator should remain constant. If vacuum advance performance is incorrect, check vacuum unit and distributor.

MECHANICAL TIMING ADVANCE (Degrees BTDC @ RPM)

Application Man. Trans. Auto Trans.
1.5L 4.2 @ 1500 4.2 @ 1500
1.5L 9.1 @ 3000 9.1 @ 3000
VACUUM TIMING ADVANCE (Degrees BTDC @ In. Hg)

Application Man. Trans. Auto Trans.
1.5L 9.4 @ 8.0 5.5 @ 7.6
1.5L 14 @ 14.9 13 @ 13.8