Manual: 2011/2012 Boxster

Page: 203

Example of Inscription


Inscription on radial tire
A – Tire size
Example: P 295/30 ZR 19 100 Y

– P - The tire is designed for Passenger vehicle.
This information is not included on all tires.
– 295 - Indication of tire width in mm
– 30 - Indication of tire height to tire width ratio in percent
– ZR - code letter for radial tires for speeds above 150 mph / 240 km/h
There are currently no standards concerning tire strength at speeds above 150 mph (240 km/h).
– R - Belt type code letter for radial
– 19 - Indication of rim diameter in inches
– 100 - Load capacity coefficient
– Y - Speed code letter
– XL (Extra Load) - Tire with increased load rating

B – TIN (Tire Identification Number)
Example: DOT xx xx xxxx xxxx
– DOT
The DOT symbol indicates that the tires comply with the requirements of the
US Department of Transportation and provides information about:
– first two-digit code means manufacture's identification mark.
– second two-digit code means tire size.
– third four-digit code means tire type code.
– fourth four-digit code means date of manufacture.
If, for example, the last four numbers read 0208, the tire was produced in the 2nd week of 2008.

C – Tire ply composition and material
The number of layers in the tread and sidewalls and their material composition.

D – Maximum permissible inflation pressure
The maximum permissible cold inflation pressure to which a tire can be inflated.

  • Do not exceed the permissible inflation pressure.

E – Maximum Load rating
The maximum load in kilograms and pounds can be carried by the tire. If you replace tires always use a tire that has the same maximum load rating as the factory installed tire.

F – Radial
The identification indicates if the tire has radial structure.

G – Term of tubeless or tube tire
Identification for tubeless tires.

Speed code letter
The speed code letter indicates the maximum permissible speed for the tire.
This code letter is shown on the tire sidewall.

T = up to 118 mph (190 km/h)
H = up to 131 mph (210 km/h)
V = up to 150 mph (240 km/h)
W = up to 167 mph (270 km/h)
Y = up to 186 mph (300 km/h)
(Y)= up to 186 mph (300 km/h) as for Y tires. Speeds of more than 300 km/h (186 mph) are also possible at a maximum tire load capacity of 85 % (confirmation from tire manufacturer required for speeds of more than 186 mph (300 km/h)).