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Engine Compression

Check compression pressure with engine at normal operating temperature, throttle valve wide open, all spark plugs removed and coil wire disconnected. Minimum cranking speed is 300 RPM.

XJ6 COMPRESSION SPECIFICATIONS

Application Specification
Compression Ratio 9.6:1
Compression Pressure 160-170 psi (11.2-11.9 kg/cm2 )
Maximum Variation Between Cylinders 10 psi (.70 kg/cm2 )
XJS COMPRESSION SPECIFICATIONS

Application Specification
Compression Pressure 225 psi (15.8 kg/cm2 )
Maximum Variation 35 psi (2.4 kg/cm2 )