Intercooler Heat Rejection Calculator

When to use it

• Compare how a change in air mass flow affects heat rejected before committing to parts, setup, or strategy changes.
• Check a workshop, dyno, simulator, or trackside spreadsheet result using a transparent formula: Mass flow × specific heat × temperature drop.
• Use the result to compare possible hardware and operating targets, then validate the setup with compressor maps, charge-temperature data, exhaust backpressure, fuel capacity, knock margin, and dyno testing.

How to use it

1. Enter air mass flow in kg/s; the default value shown is 0.4 kg/s.
2. Enter inlet temperature in °C; the default value shown is 145 °C.
3. Enter outlet temperature in °C; the default value shown is 55 °C.
4. Enter air specific heat in kJ/kg·K; the default value shown is 1.005 kJ/kg·K.

How to read the result

Heat rejected is shown in kW. Use the number as a calculated reference point, then compare it with measured data from the car, the part supplier, or the race environment. A mathematically clean answer can still be unsuitable if the inputs are estimated, rounded, measured under different conditions, or outside the normal range for the vehicle.

Assumptions and checks

• The calculator applies the displayed formula directly and assumes the entered air mass flow, inlet temperature, outlet temperature, and air specific heat are valid for the vehicle and conditions being considered.
• Changing air mass flow and inlet temperature together can move the answer in ways that are easy to miss, so make related setup changes deliberately.
• Check whether each pressure input is gauge pressure or absolute pressure.
• Leave margin for heat, altitude, turbine restriction, pressure drop, and real compressor efficiency.
• Do not size boost hardware from a single formula without checking maps and temperature behaviour.