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Is it a pollution head? If so, i'm thinking A9X, VC HDT, VH SS Group III 308s. These would not be from a standard VB-VH 308
VB 253/308 i think from the general consensus on other websites do they have the U-shaped EGR port
well you say its a 1978 cast jobbies, i'm thinking A9X or Kingswood. These aren't from a VB Commodore, they never had a hipo 308(pity!). These are like B cast heads, built before them.
I dunno about the part number, i'll have a look tomorrow night. The 11th month 78 is in the VB era, but there was still HZ Kingers and the alike still getting built.