A fwiw, going thru my older Comp catalog at solid roller lobes looking for 262 degrees duration and 0.575" lift. Their High Energy Street roller lobe 4221 calls for 0.020" lash with a 1.5 rocker ratio.
Valvetrain Tech: Lash Is Much More Than Just A Little Gap
https://www.enginelabs.com/engine-te...-a-little-gap/
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/
Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
Best time 5.13 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE