Pirelli P Zero Nero
Ripping pavement with almost any contemporary set of high-performance tires is to marvel at the grip, quiet running and durability. It's just as impressive to consider that most of these same tires are quickly heading toward obsolescence. Tire engineers continue to improve compounds, tread patterns and basic construction, and much of the important work is designing tires to satisfy the needs of very specific groups of car owners.
Just as there is an expanding market for all-season rubber-especially of the sort that can make a family sedan feel like a sports car and challenge all but the nastiest weather-the "specialty" tire segments are burgeoning with wonderful products. Pirelli, no stranger to these types of tires, has just released the latest in its venerated line of P Zero ultra-high-performance radials, this version dubbed the Nero.
No, it's not named after that infamous Roman emperor; it's the Latin word for "black" and is used to distinguish this new P Zero line from the P Zero System (yellow sidewall lettering) and the P Zero Rosso (red sidewall lettering, targeted at the O.E. market).
The Nero is essentially a replacement tire aimed at those who formerly might have chosen a tire from Pirelli's P7000 line, which is being phased out as the Nero is launched. Pirelli's cites the Dunlop SP9000 and Bridgestone S03 Pole Position radials as direct competitors to the Nero. Pricing is on par with the cost of Pirelli P Zero Rossos.
Among the Nero's distinctions is a wide range of sizes. Currently there are 29 different offerings of P Zero Nero, in section ratios from 35 to 55, diameters from 16 to 19 in., and tread widths from 195 to 275 mm (for a complete list, log on to Pirelli's special website for the tire, www.pzeronero.com).
The Nero is yet another expression of Pirelli's long history of tire development, combining the highest speed ratings, ultra-low profiles and wide section widths without sacrificing wet grip or comfort. Plus, to acknowledge the trend toward heavier, faster sports cars, within the Nero lineup are XL or "extra load" models, which feature an extra-stiff sidewall to help maintain the targeted levels of control without compromising comfort.
The essential ingredients of the Nero include a new assymetrical tread design, innovative compound, and optimized belt pack and footprint.
The tread elements were designed to provide exceptional stiffness in both longitudinal and lateral directions to reduce deformation, which contributes to better handling and steering response. The Nero is distinctive for its wide ribs and continuous uncut elements, four deep anti-aquaplaning channels, and continuous central tread for increased stability, traction and enhanced braking. The outer shoulder has compact yet wide continuous blocks for max grip during severe cornering, and the tread's transverse grooves, set at variable angles, work perpendicularly to the direction of travel to help maintain constant adhesion.
Brewing up new, better compounds is where much of the progress is being made in these new generation tires. For the Nero, Pirelli engineers combined polymers, silicas and resins for maximum grip despite changing road conditions-both at high temperatures in dry weather and at cold extremes in the wet.
The basic construction of the Nero was also refined to provide the biggest, most stable footprint under varying stresses. The Nero's overall dimensions echo a longtime approach for Pirelli in its performance line of tires, matching a stiff, low-profile sidewall with a wide footprint, which is an especially effective way to resist centrifugal tire deformation at high speeds. Newly engineered construction, the goal to improve thermal efficiency and cord tension, makes the Nero's footprint less prone to deformation when stressed, yet the tire is lighter than a typical tire of similar size.
I had the opportunity to drive a number of different cars fitted with P Zero Nero rubber at a test facility deep in the hills of South Africa a couple hours out of Johannesburg. Though the session lasted only a few hours, the state of the art test track provided varying surfaces, including wet and dry skidpad and handling and a banked oval. The P Zero Nero displayed no weaknesses and delivered a very balanced demeanor to the test cars, which consisted of front-drive, rear-drive and all-wheel-drive models.
The Nero seemed especially competent on slick surfaces, and, indeed, the pie chart that Pirelli uses to illustrate the Nero's qualities shows it to be far superior to the reference tire in wet grip. Other areas in which the Nero excelled during testing against the reference tire include wear uniformity, mileage, dry braking, wet braking and dry handling. This was accomplished while still meeting the target tire's standards for comfort and noise suppression.
This reconciling of conflicting goals means a car owner can upsize from the stock fitment yet avoid compromising the need for a quiet, comfortable driving experience. When pushed hard, the Nero responds with exceptional precision, yet in touring mode it's never harsh or noisy.
For more information on Pirelli's entire line of performance, truck and touring tires, visit www.pirelli.com.
Continental ContiExtremeContact and ContiSportContact 2
Continental Tire may not be the first tire company name to roll off the tongue of Joe Circle Track in America's heartland, but it has a long history that makes it well-known and respected in Germany and throughout Europe. However, Continental has earned recognition in the U.S. since the 1995 introduction of the ultra-high-performance ContiSportContact, which has served well as original equipment on many of the finest high-performance cars, balancing dry- and wet-weather performance with good ride and quiet running characteristics. It has been an important part of ec's favorite cars, such as the BMW 330i.
Continental Tire sees the ultra-high performance market split into three categories: summer, all-season and winter tires, which account for 35 percent, 61 percent and 4 percent, respectively, of the North American UHP market. Continental's "no-compromise" strategy is to cover each segment of the market with a directed product. Continental says that, years ago, it developed the first dedicated winter tire and now covers that area of the ultra-high-performance segment with the ContiWinterContact TS790. It recently launched two new tires, the ContiExtremeContact and ContiSportContact 2.
ContiSportContact 2
The ContiSportContact 2 is intended to gradually replace the original ContiSportContact, offering greater dry and wet performance with less regard paid to winter capability. It was designed for European customers, who generally mount true winter tires during the snowy parts of the year. It is built in Europe, and has been in customer's hands there since the latter part of 2001. As well, it has been approved for 43 OE fitments, including all Porsche models and the Mercedes-Benz E-Class. In fact, the Porsche 911 Turbo was developed on the ContiSportContact 2. OE fitments will drive the development of new sizes, which will be released as the vehicles they are used on come to market. The ContiSportContact 2 has not yet been installed on U.S.-built vehicles, which typically leave the factory with tires oriented more toward all-season capability. Continental considers its competitors to be tires like the Pirelli P-Zero Rosso, Bridgestone Potenza S-03 and Michelin Pilot Sport.
The ContiSportContact 2's tread pattern is asymmetrical, but not directional. It resembles a Formula 1 tire with its five wide, longitudinal grooves. The smoother ribs are mounted to the outside of the vehicle. Continental's modeling revealed that a continuous rib provides smoother, more even contact pressure under braking and acceleration forces than individual tread blocks. The grooves provide excellent water evacuation characteristics for hydroplaning resistance. The shoulder tread blocks on both sides of the tire are tied together, giving greater rigidity for quicker, more predictable handling and reduced noise. The ContiSportContact 2 also makes use of Continental's "Bionic" strategy both in its compound and molding and carcass technology.
Continental states that the ContiSportContact 2 is superior in every category of performance to the ContiSportContact. As well, Continental indicates that in its own testing against five competitors, the ContiSportContact 2 was the best in dry braking and wet and dry handling. Clearly, though, the ribbed tread pattern would do a good imitation of a sled if one attempted to drive with it on snow.
Driving:
Continental Tire provided european car an opportunity to drive a variety of cars with both tires in wet and dry conditions at its proving grounds in Uvalde, Texas. No competitor's tires were present, but the arrangements were excellent for subjectively feeling out the tires. It was the kind of day on which one huddles under the gas heater and looks forward to the warmth of the heated car interiors, but it was not quite cold enough to test the snow and ice capability of the ContiExtremeContact.
In the dry, the ContiExtremeContact behaved as one would expect a competent all-season tire to perform, with enough grip to provide plenty of safety if not astounding performance. The ContiSportContact 2s provided grip at least commensurate with the capabilities of the stock chassis they were mounted on. Both tires were predictable and inspired confidence when set in a turn, but the ContiExtremeContact didn't have the responsiveness nor quick turn-in of the ContiSportContact 2, which also operated at higher slip angles.
In an autocross set up on a flooded skidpad, the ContiExtremeContact performed well, but it was clear how its winter capability compromised its water evacuation properties. The ContiSportContact 2, however, was truly astounding in the wet. Even in the deep water covering the skidpad, one could turn off traction control in the Boxster and drive at a level that would be about seven-tenths in the dry. When the tires did begin to slide, breakaway was smooth and easy to recover from. I was most surprised by the ContiSportContact 2's wet braking ability, allowing me to brake later and harder than I had ever experienced in wet conditions.
More seat time will be required to experience all facets of Continental's new tires, but from this introduction, I expect they will prove highly satisfactory.
Availability:
Both tires went on sale at Continental dealers April 1. The ContiExtremeContact is available in 29 sizes, with 15- and 16-in. tires carrying a V speed rating and UTQG of 400 A A. Larger sizes are ZW speed rated and have a UTQG of 400 AA A. Seven additional sizes of the ContiExtremeContact will be available by April of 2003. The ContiSportContact 2 is available in 38 sizes from 16- to 20-in. in diameter. All carry Y, W or Z speed ratings. It will gradually replace the original ContiSportContact, which will be phased out accordingly.
ContiExtremeContact
The ContiExtremeContact is a new entry for Continental, being an ultra-high-performance all-season tire, aimed at the 61 percent UHP segment, the mainstream of American consumers. It was developed in the U.S., for U.S. customers. Continental's positioning of the ContiExtremeContact is that it is a true all-season tire, with class-leading snow capability, rather than one that just gets by in the white stuff. In addition, it would still have excellent wet traction and resistance to hydroplaning, with ultra-high-performance handling characteristics and high-speed running cabability in dry conditions.
Continental says the ContiExtremeContact's tread pattern was inspired by the rounded cross-section of a shark fin, which maintains laminar flow and glides through the water smoothly. According to Continental, by making the leading edge of the water evacuation pattern round, laminar flow is maintained and friction is reduced. Equally important is the angle of attack of the elements. Extensive siping is added to the basic tread pattern to add biting edges for snow.
The ContiExtremeContact's "Bionic," Tri-Net compound is fully silica-based, broadening the performance envelope at high and low temperatures and extending tread wear. Continental blended three compound elements, each enhancing performance in a particular area. Sulfur links give the compound stiffness for good handling and the ability to withstand high temperatures and loads. Stress-reactive links give flexibility for wet and dry grip. Low-temperature links come into play in colder weather.
Finite element modeling, a technology with which Continental has approximately 20 years' experience, was used to predict and fine-tune nearly every characteristic of the ContiExtremeContact, from achieving even contact pressure on the road to listening to the tread pattern noise.
Compared to four competitors (of course, Continental could not reveal which tires) in Continental's own testing, the ContiExtremeContact was mid-pack or better in all areas, at the top of the group in dry braking traction and approximately ten percent better than the nearest competitor in snow traction. Continental estimates that the ContiExtremeContact gives up about 20 percent in snow performance versus a dedicated winter tire.
While no OE fitments for the ContiExtremeContact have yet been approved, Continental says that such use is under consideration.