Alfa Romeo 166 Booklet page 251

Maximum speed index
Q = up to 160 kph.
R = up to 170 kph.
S = up to 180 kph.
T = up to 190 kph.
U = up to 200 kph.
H = up to 210 kph.
V = over 210 kph.
ZR = over 240 kph.
W = up to 270 kph.
Y = up to 300 kph.
Maximum speed index for snow tyres
Q M+S = up to 160 kph.
T M+S = up to 190 kph.
H M+S = up to 210 kph.
UNDERSTANDING RIM MARKING
The following are the necessary indications to understand the
meaning of the markings on the rim, as shown in fig. 7.
Example:
6.5J x 16"
6.5 = Rim width in inches (1)
J = Rim drop centre outline (side projection where the tyre bead
rests) (2)
16" = Rim nominal diameter in inches (corresponds to diameter
of the tyre to be mounted) (3 = Ø)
fig. 7
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