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Compression Pressure

At 155-165 RPM with throttle wide open. Lowest cylinder must not be less than 80% of highest cylinder. 

326" 285 HP 170-190 lbs.
389" 335 & 360 HP 170-190 lbs.
389" 256 HP 135-155 lbs.
All Others 150-170 lbs.
VALVE TAPPET CLEARANCE

All Engines Zero Lash (Hydraulic Lifters)