Porsche 911 GT3 Owner's Manual page 143

A - Tire pressure
B - Tire temperature
C - Tire pressures for cold tires
D - Tire pressure for hot tires
E - Pressure increase as the result of temperature
increase
F - Pressure drop in faulty/leaking tires
Pressure increase as the result of
temperature increase
1. Required-pressure line
2. Warning stage 1
(from –4 to –7 psi (–0.3 bar to –0.5 bar))
3. Warning stage 2
At speeds above 100 mph (160 km/h):
(from –5 psi (–0.4 bar))
142
Instruments, On-Board Computer
4. Warning stage 2
At speeds below 100 mph (160 km/h):
(from –7 psi (–0.5 bar))
In accordance with physical principles, the air
pressure changes as the temperature changes.
The tire pressure increases or decreases by
around 1.5 psi (0.1 bar) for every 18 °F (10 °C)
change in temperature.
The Tire Pressure Monitoring takes this relation-
ship between tire pressure and temperature into
account.
Tire pressure specifications
Information on tire pressure for public roads can
be found in this Owner's Manual in the Technical
Data chapter or on the tire-pressure plate in the
left door aperture.
These values apply to cold tires at 68 °F (20 °C)
ambient temperature.