Need assistance with factory engine specs.

[Warren F.]

Re: Need assistance with factory engine specs.

Joe,

Thanks so very much. My mind is much more at ease now. I appreciate everyones assistance on this.

[Clem Z.]

Re: Need assistance with factory engine specs.

i have a spring tester BUT i have no springs. when i installed them on heads i only checked them at the installed seat pressure to make sure they met the specs

[Clem Z.]

Re: Need assistance with factory engine specs.

my early march build 396,broke 3 valve springs in the short time i owned it the original springs were a disaster waiting to happen. the original keys and spring retainers were also no good because the were not hard enough. you want to use the 3947880 keys with the 627 spring kit

[Joe L.]

Re: Need assistance with factory engine specs.

clem-----

Below is a photo of one of the actual GM #3859911 valve springs that I removed from my 1968 Chevelle SS-396 with L-78. I broke several of these from the time I purchased the car new in May, 1968 until I sold it in September 1969 with about 18,000 miles on it.

I have seen folks pay Big $$$ on eBay for an engine set of these 3859911 "original, NOS springs". I hope they are buying them for "historical reference" or "wall display" and not to use on a car. Anyone that would use these springs on an engine to be run (except, MAYBE, on and off a trailer) is absolutely nuts.

[Clem Z.]

that looks familiar !!!.

they were very heavy wire and it must not have been of very good quality. like i have posted before i broke one on the way back home to Pa from picking up my corvette at the st louis plant. i was lucky as i never dropped a valve like most owners did.

[Art A.]

Re: Need assistance with factory engine specs.

Warren, I think you will find that "1823M4" is a GM Material Specification number. I'm away from my archives until April, so I can't confirm, but it looks like it is.

Art

[Warren F.]

Art...thank you for your kind reply. *NM*