3900 LZG Valve Spring Rate Data

[NateD4]

Here is some valve spring data for the 3900 LZG heads taken from the intake side.

Valve Spring Height / Measured Spring Force
1.880" / 54 lbs
1.600" / 60 lbs
1.400" / 213 lbs
1.350" / 232 lbs
1.320" / 250 lbs

hopefully I can turn up an equation to fit these so anyone interested can pick their installed heights...