C2-L78 valve springs

[Robert M.]

The engine in my 65 L78 Cpe was rebuilt once in the early 80's. It is stock and has about 3500 miles since the rebuild. As it is the original engine, and valve springs were often a weak link, I want to replace the springs with new. Are the OEM GM springs still available or is there a better product? I am sure Clem,Jack H. and Joe L. will have the answer. Thanks

[Joe L.]

Re: C2-L78 valve springs

Rob------

The original springs, GM #3859911, are no longer available and that's a good thing. These were the springs, discontinued in November, 1970, that had frequent breakage problems. I would not even consider using these springs on an engine. If I even thought that an engine had even ONE of them on it, I'd replace the whole set to make sure I got rid of it.

The current GM valve spring for the application is GM #3970627. This is the spring that replaced the 3859911 in Novemeber, 1970. These springs work just fine and are what I'd use.

[Clem Z.]

also change the retainers and valve keys

because both were too soft and caused dropped valves

[Robert M.]

Re: also change the retainers and valve keys

Thanks guys, I will follow the advice from both of you.