FREE TOOL · THERMAL SANITY
EGT estimator + safe limits
Estimate exhaust gas temperature (EGT) at the turbo inlet from AFR target and check it against safe ceilings for your exhaust hardware. Hotter is more power — until you melt the turbine wheel or crack the exhaust manifold.
Safe EGT ceilings
| Hardware | Sustained max | Brief peak |
|---|---|---|
| Cast-iron OEM manifold (petrol) | 900°C (1650°F) | 950°C |
| Stainless tubular manifold | 950°C (1750°F) | 1000°C |
| Inconel race manifold | 1050°C (1920°F) | 1100°C |
| Diesel cast manifold | 750°C (1380°F) | 800°C |
| Diesel race manifold | 850°C (1560°F) | 900°C |
⚠ Diesel runs much cooler EGTs than petrol because of the high AFR (lean). Exceeding 850°C on a diesel cracks the manifold and melts the turbine.