OCR Text |
Show Made for High-Speed Durability, not Long-Term Use Elocioo Tores no? Answer, Warns MsirDgeir AKRON, Ohio The growing use of racing tires on sports and high performance cars for street travel is a practice that should be stopped, warns the manager of racing tire development develop-ment for the world's largest rubber rub-ber company. "If you want to compete on a race track, use racing tires. But if you want extra performance perform-ance on the highway, get high-performance high-performance passenger tires. Racing tires are not the answer," an-swer," is the blunt advice of Harold E. Mills of the Goodyear Tire and Rubber Company. Major Differences "There are a number of major ma-jor differences between a tire designed for the street and one designed for racing," Mills explained. ex-plained. "Probably the most important im-portant are that race tires have no rubber sidewall protection for the carcass cord they're designed de-signed that way to dissipate heat generated at racing speeds and no protection from the effects ef-fects of weathering." A passenger car tire has thick sidewall rubber to protect the carcass from curb-rub damage. And the rubber is compounded to withstand the effects of weathering, weather-ing, or oxidation caused by exposure ex-posure to ozone and heat a tire's two worst enemies. S sort-Term Use "There are no curbs to be rubbed on a race track, and a racing tire is not expected to be in use for a long period of time," Mills noted. "On the other hand, a passenger tire is expected to withstand exposure to the elements." ele-ments." "When we design a race tire be it for stock cars, sports cars, drag racing or what-have-you our main considerations are for good handling and stability sta-bility characteristics and heat dissipation. We are not concerned con-cerned with a comfortable ride, squeal or noise factors," Mills said. "Tread wear is often only a secondary consideration, and we are only concerned with providing pro-viding wet track performance in certain sports and formula car tires. "For example, at the LeMans 24-hour race this year, Goodyear had three different tires available avail-able for dry, damp and wet conditions," he said. 200 Miles Per Hour "Our primary aim is for high speed durability," Mills continued, contin-ued, "which means producing a tire able to withstand and dissipate dissi-pate the tremendous heat encountered en-countered by a tire on a car going 200 miles per hour or faster. fast-er. A passenger car tire never encounters this kind of condition." condi-tion." The Goodyear official added that a race tire is designed for a much wider wheel than is a passenger car tire, and for best performance carries considerab ly higher inflation pressure. Abnormal Curvature "If a wide race tire is mounted mount-ed on a conventional passenger car wheel," Mills said, "the result re-sult is a small 'footprint' because of abnormal curvature of what is intended to be a wide, flat tread, and abnormal curvature of what is intended to be a wide, flat tread, and abnormal tread deflection. de-flection. The tire will wear out quickly. "And who would be comfortable comfort-able riding in a car with tires inflated to 67 to 70 pounds per square inch? No one. Inflate a racing tire to only 24 to 28 pounds average for a passenger passen-ger tire and fatigue from the excessive deflection wi1l it out in no time." Harsh Ride Characfe "A racing tire is of ,., angle construction tot and therefore has a W? characteristic," Mills , has no sidewall protect "s is not intended to hanft variety of weather Col 5 which confront the driver "'i public highway. "Take all these facw , consideration," Mills contl "and it is obviously sa? more logical to equip a Da C ger car with convention ?' designed for highway KtC ance on the highway rather J take chances with racing tir? |