Question about buying Carter BBD for my 318 (unless I should look at something else)

Bugman said

1967 intake manifold undivided single plane. couple years later single plane divided. Later dual plane divided and stayed that way. Dual plane best for lower rpm, my guess. which do you have

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Intake is 2468960 which seems to be 1967-69 (so it's the first casting made for the LA 318?)

Heads are 4027593 (1977-84) I think they have small air holes under each exhaust port that are covered by my exhaust manifolds (3830684).