I don't know if you're serious about the big block heads or not, but no they aren't anywhere near a "blowed up version of a 350 head". The small block Chevy heads all had quench pads, where a scarce few Mopar big block engines used a closed chamber head with a quench pad. The Max Wedges, the 361s, early 383s, (and one year only 350), the 440 with the 915 small exhaust valve head and the 67 HP 440 with the big exhaust valve. All the rest were complete open chamber heads. Chevy never made such.
:lol: