Bought 5.7 hemi/nag1 out of a cop car. Some questions.

I have personally used stock 6.4 valve springs on a 2010+, 5.7 eagle head, but I do not know all the nuances, if there are any. And the set on my shelf are actually 6.2 hellcat springs. Came out of the same hellcat as the cam I have. Sorry, not sure why I recalled them being 6.4. Good luck either way.

Nice! I prefer personal experience and I don't have any, so I'm just regurgitating what I read years ago. The 6.4 cam swap "recipe" says the 6.4 springs don't work. Sounds like maybe they do though.