1964 valve lash

[Mike L.]

Does anyone know the required valve lash on 64 - 327- 365hp?

[Ed S.]

Re: 1964 valve lash

intake 30 thousands, exhaust 30 thousands, - not to be sarcastic but..... that's why they call it a 30-30 cam.

[Don H.]

Re: 1964 valve lash

Mike-
Ed is a smart aleck.
It's actually .026 I and E.
Give this a read, and see if it helps you. John Hinckley and Duke Williams are experts in camshaft dynamics.

https://www.crankshaftcoalition.com/wiki/images/c/cf/30-30_cam_adjust.pdf

[Ed S.]

Re: 1964 valve lash

Don is correct on both counts, I am a "smart aleck" and....., according to the Hinckley / Williams paper, the lash is best set at .026 I & E (cold). Shop manual specifies 30 - 30 hot. Personally, I would think that making the adjustment cold would be a lot easier. Recommendation - go with the .026.

[Duke W.]

Re: 1964 valve lash

Actually, the latest revision of that paper (Sept/08) recommends .023". It's on the Web, but so are earlier versions that recommended .026". The reason for the tighter lash recommendation is explained in the paper. Also, it's critically important to use the recommended indexing scheme to assure that the lifter is on the base circle for each valve when clearance is adjusted.

Duke

[Ed S.]

Re: 1964 valve lash

Thanks for setting us both straight Duke, I should have remembered, I do have your later paper on that subject where you recommend .023, and I am sure Don is aware of it as well. We (Don & I) both need a lot of adult supervision.

[Mike L.]

Re: 1964 valve lash

Thank you Ed!

[Mike L.]

Re: 1964 valve lash

Thanx Don, I'll look into it.

[Mike L.]

Re: 1964 valve lash

Thanx Duke. What about doing it the old fashioned way, while it's running?

[Duke W.]

Re: 1964 valve lash

Sure, you can do it that way if you like getting your hands burned with hot oil and make a total mess in your engine compartment.

Doing it cold using the recommended indexing procedure to ensure the lifter is on the base circle, you can proceed at your own pace, make the final adjustment more accurate, not get you hands burned with hot oil, and not make a mess in the engine compartment... your choice.

BTW, since the steel pushrods expand at nearly the same rate as cast iron block/heads, and "hot" (idling) the exhaust valve is not sufficiently hot to cause significant valve stem expansion, I have never measured any meaningful difference between "hot" (idling) and cold. If an engine has aluminum heads and/or block, it's a different story.

Duke

[Mike L.]

Re: 1964 valve lash

Thanx Duke, cold it is!

[James G.]

Re: 1964 valve lash

I recently set my LT1 to the latest figures I found John had given, COLD LASH .021 intake .026 exhaust using the base circle method.
Are these settings still currently applicable?

[Duke W.]

Re: 1964 valve lash

No, those recommendations have been superseded. Search Hinckley Williams valve adjustment and download the Sept/08 version. Ignore previous versions, which might show up in the search.

Duke

[Ed S.]

Re: 1964 valve lash

I think the version that Duke is referring to as being the latest on solid lifter lash adjustment is attached as a PDF file.

[Mark E.]

Re: 1964 valve lash

Don is correct on both counts, I am a "smart aleck" and....., according to the Hinckley / Williams paper, the lash is best set at .026 I & E (cold). Shop manual specifies 30 - 30 hot. Personally, I would think that making the adjustment cold would be a lot easier. Recommendation - go with the .026.

"26/26 cam" doesn't have the same ring to it.