Selecting properly rated tires is important for the safe driving and proper handling of your car. The tire rating system makes it easier to compare different tires and pick the right ones.
The letter designation on a tire rating is the maximum speed for which the tire is rated. The tire size and rating will look like 225/50R16 89H, where the H designates the speed rating.
H-rated tires are rated for a maximum speed of 130mph. The V rating is the next rating faster, and V-rated tires are good to 149mph. Both H- and V-rated tires are considered to be performance-touring tires.
To support running at higher speeds, V-rated tires will have a stiffer sidewall and slightly firmer ride than H-rated tires. For normal driving conditions the H-rated tire will provide a more comfortable ride and the V-rated should give slightly better handling.
Tire speed ratings were first established in Germany in the 1980s to help drivers pick the correct tires for the high speed autobahns. The speed ratings were initially in kilometres per hour, making the conversion to miles per hour somewhat odd for certain speed ratings like 149mph for the V rating.
Tire manufacturers often offer identical tires in the same size with different speed ratings. For example, the BFGoodrich Advantage T/A in size 225/60R16 is available with either an H or a V rating. The V-rated tire will be the more expensive option.