Does a v or h rating change the performance of the tire?

The "h" or "v" rating is the speed rating on the tire.. the later in the alphabet the higher the speed rating.. h rated tires are the lowest rated and are not reccomended for high speed driving... Z rated tires are the highest rated and are reccomended for prolonged high speed driving .. think autobahn. ---------------- Beginning in 1991, the speed symbol denoting a fixed maximum speed capability of new tires must be shown only in the speed rating portion of the tire's service description, such as 225/50R16 89S. The most common tire speed rating symbols, maximum speeds and typical applications are shown below: ---------------- M

• 81 mph - 130 km/h ---------------- N - 87 mph - 140km/h ---

Temporary Spare Tires ---------------- P - 93 mph - 150 km/h ---------------- Q - 99 mph - 160 km/h --- Studless & Studdable Winter Tires ---------------- R - 106 mph - 170 km/h --- H.D. Light Truck Tires ---------------- S - 112 mph - 180 km/h --- Family Sedans & Vans ---------------- T - 118 mph - 190 km/h --- Family Sedans & Vans ---------------- U - 124 mph - 200 km/h ---------------- H - 130 mph - 210 km/h --- Sport Sedans & Coupes ---------------- V - 149 mph - 240 km/h --- Sport Sedans, Coupes & Sports Cars ---------------- When Z-speed rated tires were first introduced, they were thought to reflect the highest tire speed rating that would ever be required, in excess of 240 km/h or 149 mph. While Z-speed rated tires are capable of speeds in excess of 149 mph, how far above 149 mph was not identified. That ultimately caused the automotive industry to add W- and Y-speed ratings to identify the tires that meet the needs of new vehicles that have extremely high top-speed capabilities. ---------------- W

• 168 mph - 270 km/h --- Exotic Sports Cars ---------------- Y -

186 mph - 300 km/h --- Exotic Sports Cars ----------------