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Engine Compression

When making compression checks, disconnect ignition switch connector Pink wire from high energy ignition system. With air cleaner removed and throttle and choke wide open, crank engine through at least 4 compression strokes.

COMPRESSION SPECIFICATIONS

Application Specification
Compression Ratio
5.0L
Federal 9.2:1
Calif. 8.6:1
5.7L
Light Duty 8.2:1
Heavy Duty 8.3:1
7.4L 8.0:1
Compression Pressure 150 psi (10.5 kg/cm2 )
Maximum Pressure Variation (1) 30%
(1) Minimum reading of 100 psi.