The pre-war car industry was full of massive engines with relatively low power figures. Development limitations were the reason. But sometimes manufacturers deliberately made massive units with low power so they could have smooth driving dynamics thanks to enormous torque. One such example is Bentley’s 8-Litre unit (via Car and Driver).
With almost 500 cubic inches of displacement, this was only a six-cylinder unit with pistons diameter of sewage drains. The power output was 220 HP, an astonishing number for its day but diminutive today. Interestingly, such a massive engine was bound to be heavy, but Bentley used modern and lightweight materials to keep it reasonably light. Only 100 cars left the factory in late ’30.