McLaren P1 Owner's Handbook Manual page 196

MAINTAINING YOUR McLAREN
WHEELS AND TYRES
Tyre Markings
1. Width of tyre in millimetres
2. Tyre profile given as percentage of tyre
width.
3. Indicates that the tyre is radial ply.
4. Indicates the diameter of the wheel rim
in inches.
5. The numbers denote load index and the
letter indicates the speed rating. 93
indicates a weight of 650 kg (1,433 lbs)
and Y indicates speeds over 300 kph
(186 mph).
5.44
6. Displays the maximum load which can
be carried by the tyre.
7. Wear rate indicator. The higher the figure
the longer a tyre will last.
8. The alpha character denotes resistance
to heat. An 'A' rated tyre offers most heat
resistance.
9. Information about the manufacture of
the tyre. Contains place and date of
manufacture.
Tyres
WARNING: The tyres must be mounted
according to the labelling on the tyre
wall. The word 'OUTSIDE' must be on the
outer edge of the tyre when it is fitted to
the wheel or the stability of the vehicle
will be adversely affected, especially at
high speeds.
Asymmetric Tyres
Asymmetric tyres have a tread pattern that is
different from one side of the tread to the
other. This combination of tread offers better
grip in both wet and dry conditions.
The outer tread features a larger stiffer tread
pattern that aids with cornering stability. The
inner tread pattern aids stability in wet
conditions. A central groove in the tyre aids
straight line stability.
WARNING: Only tyres recommended by
McLaren are to be fitted to the vehicle.