.407" is the 'standard' Pontiac valve lift number
All the normal 389s, 400s, and 455s had basically that lift. Slightly differing durations depending on the application, but .407" lift across the board
As far as the Ram Air versions camshafts, I think only the RAII (.470") and RAIV (.520") had more valve lift.
They used the same 9794041 camshaft in both RAII and RAIV, but the IV used 1.65 rockers to achieve the higher lift.
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