Porsche tyre sizes and ratings

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Tyre sizes and ratings

What do the markings on the side of your Porsche tyres mean? This page explains all.

Sidewall marking
The first thing to do is decode the markings on the side of the tyre. For the purposes of this guide, we have used a 295/30ZR18 (98Y) tyre on a 11Jx18, as used on a Porsche 996 GT3. Obviously, the number on your tyre may differ but the principles hold:

295: Width of the tyre in millimetres
30: Height of the tyre sidewall as a percentage of the width. In this case 50% of 205mm. Also known as the aspect ratio.
R: Radial Construction
18: The diameter of the tyre’s inner rim in inches
98: Load Capacity of Tyre (see below). In this case it’s 615kg
Y: Speed Symbol (see below). Indicates the maximum speed for the tyre at full load. In this case 300kph.
E4: ECE type approval mark, which demonstrates the tyre has been tested as high quality by the European Regulatory Authorities.

Speed ratings
S 180kph 111.8mph
T 190kph 118.1mph
U 200kph 124.3mph
H 210kph 130.5mph
V 240kph 149.1mph
W 270kph 167.8mph
Y 300kph 186.4mph
VR 210+kph 130+mph
VZ 240+kph 150+mph

Load rating
62 265kg 84 500kg 106 950kg
63 272kg 85 515kg 107 975kg
64 280kg 86 530kg 108 1000kg
65 290kg 87 545kg 109 1030kg
66 300kg 88 560kg 110 1060kg
67 307kg 89 580kg 111 1090kg
68 315kg 90 600kg 112 1120kg
69 325kg 91 615kg 113 1150kg
70 335kg 92 630kg 114 1180kg
71 345kg 93 650kg 115 1215kg
72 355kg 94 670kg 116 1250kg
73 365kg 95 690kg 117 1285kg
74 375kg 96 710kg 118 1320kg
75 387kg 97 730kg 119 1360kg
76 400kg 98 750kg 120 1400kg
77 412kg 99 775kg 121 1450kg
78 425kg 100 800kg 122 1500kg
79 437kg 101 825kg 123 1550kg
80 450kg 102 850kg 124 1600kg
81 462kg 103 875kg 125 1650kg
82 475kg 104 900kg 126 1700kg
83 487 105 925kg