Valve Spring

Free Length (Approximately) 44.4 mm (1.747 inch)
Spring Tension (Valve Closed) 91 N @ 39.8 mm (67 lbs. @ 1.57 inch)
Spring Tension (Valve open) 239 N @ 32.6 mm (176 lbs. @ 1.28 inch)
Installed Height 40.18 (1.580 inch)