because that cooling happens before combustion making the intake air denser and the difference in kinetic energy of intake vs exhaust larger. It is a fine line

because that cooling happens before combustion making the intake air denser and the difference in kinetic energy of intake vs exhaust larger. It is a fine line since you might end up spending more energy (in terms of drag mostly) than you can recoup by making the combustion more powerful/efficient. Also, cold air does not have 'more' oxygen than hot air - its just more dense and hence has more oxygen per unit volume.