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Air Pressure/Load Adjustment for High Speed Driving (Z-Speed Rated Tires)

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Recommended High Speed Pressure & Load Capacity Adjustments

For Z-Speed Rated Tires
(tire manufacturer must confirm speed capability beyond 149 mph)
Vehicle
Top Speed		 Required Tire
Pressure Increase		 Tire Load Capacity
% of Branded Maximum		 Z-Speed Rated Tire
35 psi O.E. Example
mph km/h psi bar % of value branded on sidewall psi lbs.
118 190 0 0 100% 35.0 1000
124 200 1.5 0.1 100% 36.5 1000
130 210 3.0 0.2 100% 38.0 1000
136 220 4.5 0.3 100% 39.5 1000
143 230 6.0 0.4 100% 41.0 1000
149 240 7.5 0.5 100% 42.5 1000
155 250 7.5 0.5 100% 42.5 1000
161 260 7.5 0.5 100% 42.5 1000
168 270 7.5 0.5 100% 42.5 1000
174 280 7.5 0.5 95% 42.5 950
180 290 7.5 0.5 90% 42.5 900
186 300 7.5 0.5 85% 42.5 850
Note: Never exceed the maximum cold inflation pressure branded on the tire's sidewall.

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