No. The rocker doesn't know or car what it's made out of.
Secondly, I have never seen lash get tight when an engine heats up. So the idea of setting the lash loose cold with cast iron heads and block is wrong. I set my CI stuff .002-.004 tight cold. And then check them hot to see how much they close up.
Third, there is no way if lash that cam at .026 cold. Not for all the tea in China. If it were me, I'd start at .018 cold and then check it warm. I wouldn't go any looser than .020 hot and maybe, and it's a damn skinny maybe .022 hot on the exhaust. There is no reason to run the lash that loose. That lobe has a long slow lash ramp. Pick it up further up the lobe.
