Replacing Original 427 Valve Springs

[Douglas L.]

I need to replace the original valve springs on a 427 - 390 motor. There's a few broken dampners that are visible. The motor has not been apart and did sit for a long time. The motor now runs OK and doesn't smoke. I have GM3970627 replacement springs that have an umbrella seal attached to the retainer.

Which way do I go on the seals? Replace the old seals with like kind and use the old retainers? Use the new seals that come attached to the new retainers?

Will old style seals work OK with the new springs?

Thanks in advance for your comments.

[Joe L.]

Re: Replacing Original 427 Valve Springs

You don't want to use those springs, and now you know why. Check the archives - '71 LS6 springs are what you should use. They have integral seals.

Duke

Duke-----


The valve springs in the GM #3970627 kit are the springs used for 1971 LS-6. They were also used for all other 1970-72 Corvette big blocks. They are SERVICE for all 65-69 big blocks except L-88/ZL-1. They've been around for almost 40 years now and are definitely "tried-and-true".

The springs that folks shouldn't use and the ones that I think you're talking about are the 65-69 springs, GM #3859911. They were replaced by the 3970627.