The hulls that are built more cheaply will generally be heavier for a given length.
A tornado hull from 1987 would only be alittle less stiff than a marstom hull since there were some honeycomb tornados then. even the gugeon cedar hulls were quite stiff. the tornadoes of the 60s and 70s were much less stiff than today, but the weight was the same. unless they changed the weight over the years, but one design classes are not supposed to do that. the t hull has always been the same weight since the first boat. that # slips my mind but it may be around 70#
the supercat hulls gained lots of weight after the first 50 boats when the company was sold to boston whaler. less care given to appling the liquid resin=more resin in the lamination.
an 18 foot acat hull will be lighter than an f18 hull for 2 reasons mainly. 1-less reenforcement and bouancy needed.
2-acat can use more exotic building techniques, unhindered by the f18 rules.
i imagine the dart hawk was built to the same rules as current formula cats and therefore had hulls weighing aproximately the same as a current boat.