67 and 68 383’s are very different.
67 383 had closed chambered heads and a small CFM AFB with the narrow bolt pattern. A bodies had a one year only left manifold with the most restrictive dog leg. B and C bodies all had log manifolds on 383-4bbl
68 383 all had 906 heads with a 2806301 intake and A 625ish AVS. The a body manifold got better and all 4 bbl engines in B and C body had GP exhaust manifolds. The only 330 horsepower engine was in a road runner or super bee with no A/C. They had the 440 magnum cam, not in any other 383’s. A c-body never had a 330 horse 383.
