Density altitude
Enter a zip code or city, or click the map, to load the air there.
Click anywhere on the map to move to that spot.
Forecast model at the track
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Measured at nearest airport
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Tuning numbers
| Model | Measured |
|---|
Power is an estimate for a naturally aspirated engine, against a 60 °F, 29.92 inHg dry day. Multiply measured power by the SAE J1349 factor to correct it to 77 °F and 29.23 inHg.
Turbo
This assumes the tune holds the same absolute manifold pressure in any air, and it ignores losses in the intake and intercooler. Use it to compare days and tracks. The ratio follows barometric pressure and elevation; temperature affects a turbo engine mostly through intake heat and ignition timing, which this does not model.
Forecast
The hourly forecast appears here once a location is chosen.
| Best air | Worst air |
|---|
Forecasts past about three days are a rough guide. Check again closer to race day.
Your own weather station
Enter readings from a handheld meter in the pits. This is the most accurate option.