B-block cylinder heads?

My point about the heads earlier is that alot of early "B" engines like 67 and back 383s were the small exhuast closed chamber head like the 516 castings (no expansion cup on the end). These are a little thin on the exhaust bowl pocket near the water but will flow great with 2.08 /1.74 valves and "modest" porting. Dunno what elevation you want to run 10s at but build it to have decent driveability and around 400 ponies and just put a 200 shot on it for the extra second and a half you are looking for..... Should only have to spray on the top end anyway.