American domestic cars having large displacement engines with no horsepower to them was really just a thing until it actually mattered in the early 80's. Before the energy crisis and emissions regulations there was technically nothing wrong with building engines that way because most people were not going fast and gas stations were on every other street corner with prices below 10 cents a liter.
Allow me to use RegularCars for a moment to get the point across with a 72 Ambassador with an EVEN BIGGER engine which displaces
another liter and a half in exchange for 60 more horsepower.
https://youtu.be/NLBHDjlpm1A?t=112
That all changed in the 70's when North American automakers were getting thrashed by imports with smaller engines with equal or greater horsepower at higher economy and better combustion. For a solid 10 years a lot of blocks were retooled to still remain pretty much the same process but mechanically crippled or factory tuned to be as efficient as they could be at the expensive of EVEN MORE horsepower. The 258 for example is anemic with a dual barrel carburetor and a reverse flow head. Not enough air can get through the carb and the ports are not big enough to move exhaust gases out fast enough.