I'm not a BB expert, but those heads are common to '67-'69 396 engines. 2.06 intake valves, 1.72 exhaust valves stock unless someone has upgraded to larger valves. While they would work on your engine and get you around 9-9.5:1 with flat tops, your engine might run out of air before you achieve 6500 rpm. 5500 tops IMO.