McKellor heads that only flowed 230 cfm, 17° valve angleand almost as much on the exhaust.
Thought I would throw that out for Werby. RAIV and the 670 I believe were the only closed chamber late heads you could get and the Pontic heads that came with the 2.11/1.77s all were 14°, but as I understand the 670 was the only closed chamber. I put a set on my 400, the rest of the engine was RAIV, it had the big hydraulic originally but I got the same specs as the McKellor 10 in a solid for it. It gave a lot of the 454-455 guys hell