BBC Cylinder Head Casting #'s

[Dwight Southerland]

For a Stock class car, the 391 head is not as good as the later superceded heads, so there's no good reason to use them. For SS, the castings in the late 291 heads offer a tremendous advantage, especially for the weld & grind industry, so there's no reason to use them there, either. That's probably why no one has gone to the trouble to have them poured for volume in the last 20 years.