AKRON (July 19, 2002) — High-performance tires represent probably the fastest-growing market segment in the industry. Yet every tire dealer in the U.S. has probably heard a variation of the following:
“I've bought regular tires all my life, and now all of a sudden you tell me I need to pay extra for a tire that won't even last as long as a regular tire. What makes a high-performance tire so special anyway? How is it even different from a regular tire?”
Part of the problem is that the definition of high-performance tires varies slightly from tire maker to tire maker and can vary widely between tire makers and the motoring public, according to Bob Toth, Goodyear marketing manager for automobile tires.
“The term 'high-performance' means so very different things to different people,” Mr. Toth said. “To my dad, 'high-performance' means a long tread life.”
Goodyear, whose Eagle brand represents its high-performance line, has a very specific definition of a high-performance tire, according to Mr. Toth. This includes a lower aspect ratio (65 series or less); a wider tread as a percentage of section width; and a speed rating of H or above.
Bridgestone/Firestone divides its tires for the high-performance market into high-performance and ultra-high performance categories, according to Bill VandeWater, the company's consumer products manager in the sales engineering department.
Ultra-high performance (UHP) tires have V and Z speed ratings and generally are original equipment on cars such as Chevrolet Corvettes and Ford Mustangs, he said. High-performance tires, with speed ratings of H, S or T, are more mass-market and will have some, but not all, of the features of a UHP tire.
While not making the same market differentiation as Mr. VandeWater, Mr. Toth also noted that some tires have some HP features, but not all. Chief among these is a sporty look.
“That means the sidewall won't be a wide white, or white at all except maybe for some white letters,” he said. “It's a tastefully understated style—or sometimes an intentionally overstated one.”
But many sporty-looking tires don't even have an H speed rating, and he called this market segment the “pseudo-performance segment.”
“I might wear Michael Jordan sneakers, but that doesn't make me a world-class basketball player,” he said.
Mr. Toth and Mr. VandeWater were in total agreement on the purpose of a high-performance tire.
Whereas good tread wear and a plush ride are the hallmarks of a mass-market tire, they said, steering precision and maximum handling are the most desirable characteristics of an HP or UHP tire. Therefore, the materials, design and engineering of an HP tire are very different from those of a regular tire.
* Tread. A high-performance tire has a more aggressive and asymmetrical tread pattern than a mass-market tire, to enhance precision and maneuverability, Mr. Toth said.
“The tread compound is designed for optimum performance in less-than-winter conditions,” he said. “We're talking spring, summer and fall driving. When the temperature drops substantially below freezing, the traction drops off.”
UHP tires, according to Mr. VandeWater, have directional tread patterns designed to channel water from under the tread and prevent hydroplaning. “There are no sipes in those tread patterns, because that takes rubber away from the road,” he said.
Unlike mass-market tires, the treads on UHP tires are designed specifically for the left and right side of the vehicle, which creates major problems if they're mounted incorrectly, Mr. VandeWater said.
“With mass-market tires, you can just flip them over and mount them as you please,” he said. “But with directional tires, you can't do that. The V-pattern of the tread moves water from inside the tire to outside it, and if you do it backwards, you draw water under the tire, increasing the chances for hydroplaning.”
* Construction. Mass-market tires, Mr. VandeWater noted, have bodies made almost entirely of polyester, which is pliable and durable for a soft ride and long life. Most HP and UHP tires, however, contain nylon or rayon.
“Nylon and rayon have better heat properties than polyester and can absorb shock better,” he said.
Also, HP and UHP tires probably will have a harder bead filler than regular tires—“as hard as your desk,” Mr. VandeWater said. “Hard fillers improve response. When you turn the wheel, your tire moves with it.”
In UHP tires, you often will find extra reinforcement—of nylon or even steel—along the bead. “At 130-plus mph, a standing wave starts that could cause a tire to self-destruct,” Mr. Toth said. “A stiff sidewall makes a tire capable of high speeds.”
Extra bead reinforcement is very common in Europe, where motorists often drive on the highway at 150 mph, but less so in the U.S., according to Mr. VandeWater.
Also because of the high-speed factor, an HP tire will be “slightly non-radial, slightly angle-ply,” Mr. Toth said. “It will have 90-percent radial construction, but there will be extra stiffness from the cross-ply structure as seen in the old bias tires.”
Nylon cap plies are a construction feature that became notorious during the Ford-Firestone recall controversy. Consumer advocates and plaintiffs' attorneys made an issue of them, insisting that all tires should have cap plies for safety. Mr. VandeWater, however, reiterated the tire manufacturers' position that cap plies are necessary only on tires designed to be driven at very high speeds.
“Cap plies are universal on ultra-high performance tires,” he said. “When you get to 125 or 130 miles per hour, centrifugal force tends to pull belts off, and cap plies prevent this. They're not for safety, just for speed.”
In some UHP and Z-rated touring tires, such as those used as OE for Mercedes-Benz and BMW, aramid is used as a belt material. It is extremely strong and lighter than steel, Mr. VandeWater said, but its high cost prevents its wider use.
Aspect ratios can go as low as 30 for UHP tires, with widths in the 305-315 range. This compares with 55-60 and 235-245 for HP tires and 65-70 and 215-225 for mass-market tires, Mr. VandeWater said.
“The taller the sidewall, the greater the shock absorption,” he said. Taller sidewalls are desirable in mass-market tires, where you want as smooth a ride as possible, but not in UHP tires, where drivers want to feel the road.
* Marketing high-performance tires. When you consider mass-market vs. high-performance tires, you consider a series of design tradeoffs, Mr. Toth and Mr. VandeWater said. Tire dealers must keep this in mind when they discuss HP tires with possible buyers: What kind of performance is this buyer looking for? Does he want long tread life and a cushy ride, or great traction and responsiveness?
A tire dealer should stress that the OE tire on even a Corvette won't necessarily be the tire that gives the best performance, Mr. VandeWater said.
“The auto maker has a whole list of priority items for tires, but on the top of that is fuel economy,” he said. “He has to sacrifice a few handling features for fuel economy, but the aftermarket buyer isn't as concerned about that. The guy who bought the Corvette and hoped to get a little more handling out of it can get it in the aftermarket. He won't get the fuel economy or the tread life, but he's a little more knowledgeable about tires and high-performance vehicles, and he's willing to accept that. You have to identify that kind of driver when he walks through the door.”
For Mr. Toth, selling high-performance tires means persuading customers that there's more to a tire than just good tread wear and a soft ride.
“What high performance is all about is enhanced vehicle maneuverability,” he said. “We construct and design tires for that. When you think about it, all tires are high-performance in that there are certain thresholds of maneuverability we don't go below. When you compromise those for long tread wear, you are cheating your customers and compromising their safety.
“Responsiveness, stopping, starting and cornering are more important, ultimately, in my book than tread wear,” he added. “When I'm stopped at a stoplight, I feel more confident if I know the guy behind me has high-performance tires.”