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It is the same as L78.

From memory it is 0.024 intake and 0.028 exhaust but let me see if I can find the L72 Sun tune up sheet. Set "hot and running". You can go a little tighter than that - say 0.022 and 0.026 to see if it likes that any better.

Setting them cold is similar to the procedure for the 30/30 cam. Set cold numbers a bit tigher if you are using stamped stock rocker arms.
http://www.camaros.org/302valves.shtml

Let's see what others say.
 

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If you are going to set it cold, you will need to be a little tighter, since it will loosen up when hot. ...

Let's see what others say.
:D I'd say that clearances get 'tighter' as an engine heats up - not 'looser' ;)
As the metal in the valve train expands the lifter, pushrod, and valve stem elongate - taking up clearance in the system.

If setting cold, add a 'couple-thou' (@.002") to the "HOT" setting and recheck once the engine has reached operating temps.

IIRC, the lash settings given are correct - or close enough.
Some of the higher HP BB's recommended a slightly tighter Exhaust (@.026" vs. .028") but the Intakes were almost all the same at .024"

But - lets see what others say :yes:
 

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:clonk:
It's early...

I will go back and change that wording...

Hot is best, but this is from that article I linked to above...

...an alternate method of obtaining the required lash dimension for a given solid-lifter setup is to accurately hot-lash the valves to the cam manufacturer's specifications, allow the motor to cool, immediately re-measure the lash while cold, then use that cold lash measurement for subsequent cold lash setting.
 

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Per the '69 chassis service manual, 427/425 should be .024 and .028 at operating temp. That may not apply if the cam and lifters are a retrofit grind...
 
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