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Engine Compression

When making compression checks, disconnect ignition battery voltage connector from ignition coil. Remove air cleaner. Hold throttle and choke wide open. Remove all spark plugs. 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.