KPMI, valve spring kit. .415" lift. Steel top collars

Reduces total valve train mass. Great for OEM rebuilds with stock specifications. The springs are manufactured from the highest quality clean chrome silicone wire, shot peened and heat treated for maximum fatigue life. Kit includes springs, upper collars, lower collars, and valve keys. Max valve lift: .415". Installed height: 1.375". Seat pressure 129 lbs. Open pressure: 272 lbs. @ .415" valve lift. Note: With .565" diameter valve guides.