SANTA BARBARA, Calif.-Advances in rubber compounding and casing design lie behind the improvements in treadwear and wet and winter traction in the new generation of Bridgestone Turanza touring tires. Bridgestone/Firestone Inc. debuted the redesigned radials to the press and selected dealers in two separate ride-and-drive events in the Santa Barbara area, Feb. 19-22.
In redesigning its best-selling Bridgestone line, BFS added a Z-speed-rated model, which it believes is the first Z-rated radial to carry a limited treadwear warranty (40,000 miles).
The company also has upgraded the treadwear warranty on the T-rated Turanza, replacing the original 80,000 miles with a ``lifetime'' warranty, good for as long as the original purchaser owns the vehicle.
According to Art Michalik, marketing manager for Bridgestone consumer products, the original Turanza line, introduced in 1989, was among the first true touring tires, developed in response to automakers' introduction of touring cars: sedans with increased levels of performance, approaching that sports cars, but with a much smoother ride.
Touring tires seek to combine the smooth, quiet ride of a premium passenger tire with the responsive handling of a high performance tire.
The new Turanza was designed to maintain those characteristics while significantly improving treadwear/tire life and all-season capability, especially wet traction.
According to BFS engineers, the new Turanzas wear, on average, 20-percent longer than the original versions and show improvements of 7 and 10 percent, respectively, in wet and winter traction.
According to Phil Pacsi, Bridgestone product information and education specialist, these improvements are primarily due to two new Bridgestone technologies: ``long link carbon black (LL carbon)'' and ``contour optimized casing shape (COCS).''
LL carbon is a new type of carbon black composed of longer-chained carbon structures, as opposed to the more traditional grape-like clusters. The long-chained carbon resists cracking, which improves treadwear and rolling resistance.
The tread compounds of the Turanza H, V and Z also contain silica, which further enhances treadwear and improves wet traction over a wide range of temperatures, Mr. Pacsi said.
COCS is a computerized, evolutionary method of design that, in this case, results in a rounder shape for the tire profile. This shape, combined with a softer bead filler, produces a more comfortable ride, while contributing to better traction and handling.
The new Turanza also employs Bridgestone's ``five pitch noise reduction technology,'' which uses an alternating tread block design to create specific sound ``phases'' that cancel each other out.
The new tires also feature a rounder bead, which results in a rounder mounted tire, and keyhole sipes, which are wider at the bottom to maintain wet performance as the tire wears, Mr. Pacsi said.
They are available in a wide variety of sizes, in aspect ratios from 55 to 75, to fit rims from 13 to 16 inches in diameter. The Turanza T is available in 22 different sizes; the Turanza H, 13; the Turanza V, five sizes; and the Turanza Z, two sizes-P225/60ZR15 and P225/60ZR16.
The tires come with Bridgestone's ``Platinum Pact Warranty,'' which includes a 30-day trial period, during which they can be returned for any reason for a refund or replacement, plus free lifetime replacement-with no proration-for any manufacturing defects.
The Turanza T's lifetime treadwear warranty-similar to the one Goodyear recently introduced on its Infinitred passenger radial-offers a free replacement if the tire wears to 2/32-inch of tread within the first three years.
Thereafter, it offers a new tire at a 50-percent discount, for as long as the original purchaser owns the vehicle.
The new Turanza will be sold exclusively through BFS' ``family channel'' of distribution, comprising its company-owned stores and affiliated independent dealerships, Mr. Pacsi said.
Print ads for the new tires are scheduled to appear in car enthusiast magazines, some general-interest magazines and the tire trade magazines.
They will feature photos of Turanza-shod cars driving on old cobblestone streets in Savannah, Ga., with the slogan: ``Cobblestones are now paved.''