Tire Test Results

Tires Tested

Pirelli P Zero (PZ4) (Max Performance Summer)

The bead wire is the foundation of the tire and creates the primary connection between the tire and the wheel, transmitting forces exerted on the tire upward to the driver and relaying steering inputs from the driver down to the tire’s footprint. The P Zero (PZ4) utilizes one of two Formula 1-inspired bead designs, providing the ability to choose between increased ride comfort and ultimate high-speed handling. Wrapping around the bead wire and defining the shape of the tire, the casing contributes to ride comfort, handling and durability, and Pirelli engineers have the option to utilize a two-ply polyester or a one- or two-ply rayon body casing with either a symmetrical or an asymmetrical structure when tuning the P Zero (PZ4) for Original Equipment duty. The maximum sustainable top speed of a tire, in addition to its high-speed stability, is influenced by the reinforcement located above the belt package. This reinforcement is the final internal tuning "lever" available to Pirelli, with a hybrid nylon-Kevlar ZeroDegree cap ply in either medium or high stiffness serving to keep the belts anchored under the extreme centrifugal force experienced at high speeds.

The tread design is the only element in the customization equation that is visible to the naked eye. The P Zero (PZ4) is manufactured in one of two patterns, determined by whether the tire will be used on a sports car or a luxury vehicle. The inner section of both available tread patterns features the same comfort- and wet performance-focused block design comprised of a high silica content rubber compound for additional wet traction. The Sports Car design is a dual-compound tire, with a low-void, blocky outer shoulder architecture intended to increase tread stiffness for lateral stability during high speed handling. The outer tread compound utilized in this application is one of two high-performance designs, either a street-tire based compound focused on coming up to temperature quickly and operating best in a medium-high temperature range for consistent handling, or an extra-sticky, motorsports-derived blend for ultimate performance and the ability to handle high temperatures. The Luxury Saloon tire’s outer shoulder features the same, high-silica rubber compound as the inner shoulder, molded into a pattern engineered for low rolling resistance, low noise and improved treadlife.

To demonstrate the on-road manners and outright performance capabilities of the new P Zero (PZ4), Pirelli invited select members of the Tire Rack team to experience production-spec tires during the official product launch in Estoril, Portugal.

Performance First

What better way to test the limits of a Formula 1-derived tire than behind the wheel of several high performance vehicles around the 13 turns of Estoril Circuit, a 2.6-mile race track and home of the F1 Portuguese Grand Prix from 1984 to 1996. Our drivers were exposed to several different versions of the new tire through back-to-back, lead-follow laps behind the wheel of an Audi R8 V10 Plus, Ferrari 488 GTB, Lamborghini Huracan LP 580-2 and Porsche 911 Turbo S. Though there was not sufficient driving time to explore every nuance of each car and the track to discern differences from one tire spec to another, the overall capabilities of the P Zero (PZ4) as a whole left our testers impressed.

Controlling the performance of vehicles of this caliber on a track presents a challenge to any street tire, but the P Zero (PZ4) handled the task with aplomb, matching the composure of these thoroughbred machines and allowing each automobile’s personality to shine through. Though each of the four cars arguably qualifies as a supercar, they all have a different approach to the business of speed. The first car driven was the Porsche 911 Turbo S, which features a rear-mounted, twin-turbo six-cylinder engine and all-wheel drive. The immediacy of the power delivery and the massive torque available propel the vehicle to high speeds rapidly and require a tire with suitable grip to put the power down during acceleration and confidently slow the vehicle from speed before turn-in. In this regard, the Pirelli tires proved to be a good match for the Porsche, providing authoritative stopping power and reassuring pedal feel before entering turns and allowing the driver to quickly get back on the gas at corner exit.

The next car in our drive rotation was the Audi R8 V10 Plus, a vehicle with a mid-mounted V10 and all-wheel drive. The grip from the P Zero (PZ4) tires combined with the Audi’s sophisticated all-wheel drive system redirecting torque meant traction was not a concern. The high level of available lateral grip at elevated speeds meant the turn five kink could be taken flat-out, and through the wide, constant-radius turn 13, front and rear traction felt evenly balanced, producing a well-mannered, complete package that built driver confidence.

The Ferrari 488 GTB came next, with rear-wheel drive and a twin-turbo V8 mounted amidships. The turbo motor provided sufficient torque to challenge the tires in a straight line, and the high cornering speeds meant the tires had their work cut out for them to keep the car planted mid-turn. The synthesis of the Ferrari’s chassis partnered with the P Zero (PZ4) tires created a package that felt the most balanced of the cars, working together to produce seemingly effortless speed as the individual components blended into a cohesive whole.

Finishing the group of test vehicles, with a mid-mounted V10 and rear-wheel drive, and also representing the fourth of four powertrain configurations, was the Lamborghini Huracan LP 580-2. The Lamborghini’s V10 was (relatively) light on low-end torque, but the power built in a sudden rush as the tachometer spun toward redline, and it took all the available grip from the P Zero (PZ4) tires to transfer the engine’s energy to the track through only two driven wheels. The Lamborghini-specific 305/35R19 Pirellis proved up to the task, with only one brief intervention of the traction control on the main straightaway. Turn-in was responsive, with confident front end bite as the driver was trailing off the brakes and sufficient lateral grip from the rear to roll on the throttle and accelerate away from turns.

Street Friendly, Too

The afternoon of our test day was set aside to experience the P Zero (PZ4) tire’s on-road manners, and to demonstrate this, Pirelli arranged a scenic drive along the Atlantic coast, around winding mountain roads and through the narrow, historic streets of the towns surrounding Portugal’s capital city of Lisbon. This portion of the test utilized vehicles shod with the Luxury Saloon version of the P Zero (PZ4), and the Tire Rack team’s drive was spent behind the wheel of a 2016 Jaguar XF S. When road testing tires in a luxury vehicle like the XF S, the well-insulated cabin’s effect on isolating the occupants from any harshness caused by the tires must always be taken into consideration. With this in mind, the P Zero (PZ4) nonetheless proved itself a pleasing complement to this scope of automobile. The ride was sporty, but not overly firm, and bumps, dips and potholes were handled in a single event with no secondary motion after the initial impact. Turn-in response for street driving was crisp and linear, allowing the driver to dial in the exact amount of steering needed through a turn or to avoid a pothole. Feedback through the steering wheel was somewhat muted, and tire noise was nearly non-existent, but these two factors were likely as attributable to the test vehicle as the tires. Final judgment in all categories will have to wait until we can put the tires through their paces on our test vehicles during our normal testing season.

Conclusion

We often compare a vehicle’s tires to the shoes on your feet. Choosing the appropriate footwear for any activity is imperative if you’re targeting optimal performance; you wouldn’t wear work boots to run a marathon, after all. The Pirelli P Zero (PZ4) takes this concept a step further. Not only are they the equivalent of running shoes for a marathon, they are running shoes that have been custom-fit to the runner. Our brief introductory experience indicates the new P Zero (PZ4) is a capable performer, well-matched to the exotic machinery sampled during our evaluation. The tire is not intended exclusively for vehicles with six-figure price tags, though, and the Audi A3 is the first of many anticipated fitments for vehicles that are more mainstream and attainable to the masses. Non-Original equipment tires also will be a part of the lineup. Standard replacement tires will feature a single, high silica content compound across the face of the tire, with Run Flat tires utilizing the Luxury Saloon tread design and non-Run Flat tires featuring the Sports Car pattern. We’re anxious to test the replacement tire offering through our Real World Road Ride and Performance Track Drive when those tires become available. Watch for a full comparison test coming in the summer of 2016.