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Engine Compression

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

COMPRESSION SPECIFICATIONS

Application Specification
Compression Ratio
5.0L 9.3:1
5.7L 8.3:1
7.4L 7.9:1
Compression Pressure 150 psi (10.5 kg/cm2 )
Maximum Pressure Variation (1) 30%
(1) Minimum reading of 100 psi.
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