There are tire engineers out there who don't much give a hoot about tire speed ratings. "It's not even a government regulation," says one. "There is no government test for speed ratings. The only speed-related test is euphemistically called a 'temperature resistance test,' and it's built around the ability of a tire to disperse heat successfully under controlled conditions on an indoor test wheel."

A tire's speed rating, the engineer says, tells us nothing about the performance of the tire, its handling ability, its ride characteristics or the noise it makes. "Read a tire dealer's website, and you'll find the same disclaimer. In my opinion, there is no reason to build a tire with anything more than an H-rating for use in the U.S."

Point taken. Whether that's right or wrong is open to debate. What we do know is that federally mandated tire safety standards issued back in the late 1960s forced us to make better tires. During this same period, speed-rated radials from Europe were catching on big. The combination of new tire safety laws and speed-rated radials from Europe provided a swift kick in the pants to the U.S. tire industry just when it needed it.

But that was decades ago. Today, Tire Kingdom's website says this about tire speed ratings: "Tire speed ratings do not imply that vehicles can be driven safely at the maximum speeds for which the tire is rated, particularly under adv...