bbc head id help

[rreistino]

i have a set of rectangle port 3919840 heads prod dates H37 and K17 i have an idea of what they are they were on my car when i bought it im rebuilding my motor and swapping heads just trying to figure out what there worth

[oldandtired]

67-69 rectangular 107 cc closed chamber 396/427.
Hard to get them to flow because of the steep sides.