Pirelli 'autographs' prestige OE tires

GENEVA, Switzerland (March 6, 2013) — Pirelli Tyre S.p.A. has begun "autographing" P Zero OE tires for prestige cars, marking them to show the rubber used has been developed specifically to suit vehicle.

The practice—similar to the Tire Performance Code (TPC) General Motors Co. requires of OE tires supplied for its vehicles—seeks to show car owners that the OE tires have been homologated to cater to the individual needs of each model, so that it also becomes the default choice for aftermarket replacement, Pirelli said.

Pirelli is showcasing the markings at the Geneva Auto Salon on new ultra-high-performance offerings from Ferrari S.pA., Lamborghini S.p.A., Maserati S.p.A. and McLaren Automotive Ltd. Pirelli uses MC1, for example, for McLaren.

Each evolution is tailor-made for the individual requirements of every specific model, Pirelli said, meaning there no longer is a single P Zero designated as OE. Instead there now exists a family of bespoke tires with common ancestry.

Pirelli claims there have been 250 homologations of the P Zero line since its introduction in 2007; today there are roughly 130 versions in production, in sizes ranging from 17 to 21 inches rim diameter and aspect ratios of 25 to 50.

The P Zero uses special nano composites in the tire compound and bead to enhance ride comfort and sporting performance, Pirelli said. The tread pattern's three wide longitudinal grooves are designed to deliver grip on damp surfaces while also guaranteeing acoustic comfort. The tire's asymmetric profile provides regular wear, according to the tire maker.

Pirelli also intends to extend this autograph practice to the Cinturato P7 line, a high-performance ecological tire designed for cars of medium to high engine capacity.

Among the product launches at the 2013 Geneva Auto Salon using Pirelli tires are:

Ferrari's "LaFerrari" gasoline-electric hybrid model. The two seater, powered by a 6.3-liter V12 normally aspirated engine that delivers 800 hp, coupled with a 163-hp electric motor, runs on PZero Corsa Asymmetrics, size 265/30-19 size front and 345/30-20 rear.

Pirelli claims its researchers, working closely with engineers from Ferrari, have increased the tire's contact patch to help reduce understeer and improve turn-in and grip.

To obtain the best synergy between the tire and suspension, Pirelli differentiated the stiffness of the inner and outer shoulders by about 5 percent to ensure grip and maximum performance stability in all usage conditions.

Lamborghini Aventador LP 700-4 Roadster, a $455,000 two-seater with a "plus-one" front-rear treatment: 255/30ZR20 front and 355/25ZR21 rear.

The car's 6.5-liter V12 is rated at 690 horsepower, delivering 0-62 mph acceleration in just three seconds and a top speed of 217 mph.

Pirelli said it used special casing and belting materials and firmer compounds—a design that limits the tire's deformation and maintains the performance and rolling characteristics in all conditions—to meet the needs of the car's four-wheel drive system.

Maserati Quattroporte, for which Pirelli engineered lighter-weight P Zero tires to help keep the overall weight of the four-door luxury performance car down. Pirelli engineers reduced the mass of the belt package, which dropped the weight of each tire by 5 to 7 percent. The tires also deliver 15-percent less rolling resistance than conventional tires, Pirelli said.

Maserati offers two tire packages on the Quattroporte—245/45/19 front and 275/40/19 rear and 245/40/20 front and 285/35/20 rear—and Pirelli said it is developing a 21-inch version that should be available in a few months.

The 4,200-pound Quattroporte is powered by 530-hp engine that yields a top speed of 190 mph.

McLaren P1, which uses PZero Corsas 245/35ZR19 front and 315/30ZR20 rear.

Pirelli said the tires for this two-seat, mid-engined car are designed to deliver maximum stability and handling for a car with a top speed of 223 mph.

Among the specific features of the Corsas for the P1 are:

• Asymmetric profile on the front tires to optimize aerodynamic downforce. The asymmetric design allows the tire to remain sufficiently rigid even when subjected to different weight transfers, Pirelli said.
• Asymmetric bead design on the rear tires to help withstand lateral forces of up to 2g under acceleration and through corners.
• Innovative compounds processed with Pirelli's "ground-breaking" mixing processes to improve stability and resistance to stress.

Pirelli makes the various PZero models at its plant in Settimo Torinese, near Turin, which uses the firm's "Next Mirs" robotic tire manufacturing technology.