Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Valve Spring






Valve Springs Compression Pressure (Lb. @ Spec. Length)
Intake and Exhaust (Installed Load) 71-79 @ 1.52 inch
Intake and Exhaust (Non Turbo) (Open) 128.1-141.6 @ 1.12 inch
Intake and Exhaust (Non Turbo) (Closed) 66.5-73.5 @ 1.52 inch
Intake and Exhaust (Turbo) (Open) 151.9-165.9 @ 1.12 inch
Intake and Exhaust (Turbo) (Closed) 71.3-78.7 @ 1.52 inch
Free Length (Approximate) 1.877 inch
Assembled Height 1-17/32" - 1-19/32"
Service Limit 5% Pressure Loss @ Specified Length
Out of Square Service Limit 5/64 (0.078) inch