Ported X head pics

LOL! you mean they were lower due to inconsistent combustion chamber volume...?

No, the chambers were larger and relatively consistant. People take internet postings as fact, but us old timers who actually measured things and can remember how things were back in the day, can tell you the real deal if you care to listen. NHRA minimum chambers are not as cast, but the smallest chambers legal for "Stock" and "Super Stock" class racing. See post #26