An internal combustion engine wherein a thermo potential heat flow in combustion is maximized by providing a feedback of an optimized amount of thermo potential heat flow that is modulated in the exhaust media, into the air intake, and a method of providing feedback comprises producing a shock wave of pulse of exhaust media and pulse of intake air on the opposite side of a high temperature shock tube thereby transferring the thermo potential heat energy flow from the exhaust media to the air intake.