Hi!
Maybe someone can help me out.
I just bought a GEN VI 502 MPI where the manifolds had leaked.
So time for a valve job now.

Today I tried measure valve spring installes height and spring free length.
Recommended fpr gen6 502 should be installed height 1.88, free length 2.15

I now had installed height 1.96 and free length 2.26 @all of them.
Any chance the springs are not the stock ones? are double springs.





Thank you guys!

Double check, but i believe they use
GM 14097002 springs.
See here:
https://www.gmperformancemotor.com/parts/12562920.html

”This high performance valve spring has an outer and inner spring. Used in late model 454 and 502 HO engines. Technical Notes: The dual spring is 1.487" O.D. diameter 1. The pressure at installed height is 110# @ 1.88". Use with valve spring retainer P/N 14096274.”

If you have a 1.960" installed hgt they are probably not the stock springs, at least not from what I have seen. Post a picture of the springs and retainers.

Thanks for your replies!
yes they were instaled at 1.960. I thought this would be due valve wear and took the springs out, measured the free length and discovered them to have free length of 2.26 wich would be longer than they should be. I think springs should get shorter after time, but longer?! think they are not stock. I post picture today.