EGT (Exhaust Gas Temperature) measurement provides critical data for engine tuning optimisation, particularly valuable when jetting carburettor-equipped engines to achieve optimal air-fuel ratios across varying atmospheric conditions. This temperature reading, taken at the exhaust port, directly reflects combustion efficiency and mixture richness.
EGT reading interpretation:
- Low EGT (below 550°C): Indicates rich mixture, safe but sacrificing power
- Optimal EGT (580-650°C): Suggests ideal mixture for maximum power
- High EGT (above 680°C): Warns of dangerously lean mixture risking engine damage
Temperature readings vary significantly between engine types, with two-stroke karting engines typically operating in the 580-680°C range under racing conditions. Monitoring EGT helps identify when re-jetting becomes necessary due to changing weather, as temperature and humidity affect air density and optimal fuel delivery. Professional teams often log EGT data alongside other parameters through data acquisition systems, building databases correlating jet sizes with atmospheric conditions and track requirements. Regular EGT monitoring during testing helps establish baseline settings, then quick checks during race weekends confirm the engine remains properly jetted as conditions fluctuate.