Does anyone care to elaborate?

The simple answer to your question is definitely not.
Starting at the beginning, if you put 1 liter of ideal fuel air mixture at atmospheric pressure in a sealed container and ignite it, the heat released by combustion will raise the temperature and pressure inside the container. Measure the heat released until the pressure inside the container returns to atmospheric and you will have the theoretical maximum amount of energy that can be converted to work. In the old days this was done in a thing called for obvious reason a bomb calorimeter. No mechanical device does a very good job of converting all of the heat to work.

Starting the same volume of fuel air mixture, add some energy to compress it, the more the better. Ignite the mixture, remembering it is the same amount of air and fuel and allow the mixture to do work against a piston. Up to a point the greater the distance the piston travels the more work can be captured from the expanding gasses. Connect the piston to a crankshaft and you have converted chemical energy to rotary motion.

For a given displacement and compression ratio, without supercharging there is a theoretical maximum amount of torque an engine can produce. A 1000cc engine can burn at most 1000cc of fuel air mixture per power stroke. Once you have reached that limit the only way to increase the power available is to increase the displacement or increase the rpms. If you are designing to a displacement limit increasing the rpms is the only option.

The unit you are looking for to compare the efficiency of engines is brake specific fuel consumption.

Gives a much better explanation that I can and has some interesting numbers to consider.