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Pirelli Police Tires

Written by Ed Sanow

Replacement tires may not be on the highest priority for fleet managers, at least, not until tire wear, tire performance or tire availability becomes an issue. For budget reasons, most fleet managers want to know how long the tires last and what the state contract pricing is. To reduce complaints from patrol officers, some managers want to know how the tires perform on the street. A few managers might want to know what other brands are available on the state bid. In some cases, the availability throughout the jurisdiction is of interest.

In the past, virtually every one of these tire concerns was answered with one word: Goodyear. They performed well, had reasonable tire wear, were on nearly every state bid, and were available everywhere. And they had over 95% of the police fleet market. Other brands existed, some were even OEM options, and some were actually used by departments on their patrol cars: General XP2000 V4, Firestone FireHawk PV41 and BFGoodrich Touring T/A VR4. However, the easiest answer for all things black and round with tread was Goodyear.

All of that has changed for the 2006 model year. The Ford CVPI comes with Goodyear tires, although the exact Pirelli tire used by Ford on the Mustang GT was initially considered. The Impala comes with Pirelli tires. The Tahoe comes with General tires. The Charger and Magnum come with Continental tires. (Continental owns General Tire.)

Change is definitely in the wind. Due to the small police tire market and other uncertainties in the long-term police tire supply chain, the police tire market is now wide open. The prudent fleet manager will both keep up with these changes and keep the options open. Better yet, the alert fleet manager will get a set of optional tires for each vehicle type and put the department’s EVOC instructors to work evaluating them. With 75% of the police vehicles being the Ford CVPI, prudence demands a look at alternative V-rated or W-rated, 17-inch tires.

To smooth the transition to Pirelli tires, especially for police replacement tires, Pirelli will handle state bids and GSA bids, and they will also do stand-alone contracts for cities and counties. They will ship factory-direct to 1) a police central distribution warehouse, 2) a local Pirelli dealer, 3) a regional Pirelli warehouse, and 4) direct to the police garage, post or barracks. With a police account, they will guarantee shipment of the police tire to whatever location within 36 hours.

Pirelli Option for the Ford CVPI

Pirelli makes a W-rated, 17-inch tire that will physically fit the 2006 Ford CVPI, the Pirelli’s P Zero Nero M+S. (Nero is Italian for black.) To be clear, this Pirelli tire is not a current OE option from Ford for the CVPI, but for many reasons, fleet managers need to know this aftermarket replacement tire exists for the CVPI.

Pirelli may be a new name to many in police fleet management, but they have been making car tires since 1905. In 2005, the Milan, Italy-based tire company celebrated its 100th anniversary of automotive tire production. The same 1980s and 1990s string of World Rally Championship events that made the Audi Quattro famous were all won on Pirelli tires. The Pirelli is currently the OE tire on many Ford, DaimlerChrysler and General Motors vehicles.

The P Zero Nero is a recently developed tire but it is not new, i.e., it has a solid track record. The P Zero series of Ultra High Performance (UHP) tires began in 1987. The P Zero Nero was introduced in 2004 with two versions. One version was a summer tire (non M+S) for the Audi Quattro. The other was an All-Season (M+S) tire specifically developed for the American market and introduced on the 2005 Mustang GT. The P Zero Nero M+S is the first All-Season tire in this ultra-high performance end of the Pirelli tire line.

The P Zero Nero M+S has an asymmetric tread pattern with larger shoulder blocks on the outside edge for cornering, a continuous solid rib in the center for tracking and turn-in responsiveness, and channeled tread blocks for water movement on the inside. Since these are asymmetric (like the Eagle RS-A), be certain the outside edge of the tire is on the outside edge of the wheel!

Survey Says…

All surveys are, by definition, subjective if not emotional. The basic premise is that if you get enough responses, then two things happen. First, the extreme and directly opposite views will cancel themselves out, leaving the truth somewhere in the middle. Second, overall trends become clear. The survey may not show hard and fast, measurable results, but they do indicate credible and useful trends.

The Tire Rack, the nation’s major performance tire wholesaler, has online survey capability with feedback in 11 categories: 1) dry traction, 2) wet traction, 3) hydroplane resistance, 4) light snow traction, 5) cornering stability, 6) steering response, 7) ride comfort, 8) noise comfort, 9) tread wear, 10) deep snow traction and 11) ice traction. On their scale of 1 to 10, the rating of 1 is Unacceptable and 10 is Superior.

A caveat applies to these results. The P Zero Nero M+S is made in both Europe and Brazil. The European-made tires use a stickier tread compound, have better wet and dry traction, and poorer tire wear. The Brazilian-made tires use a harder compound, have better tire tread life but not as good traction as the European version. The Tire Rack survey does not distinguish between manufacturing locations. Instead, all P Zero Nero M+S results are lumped together.

In use by a wide cross-section of tire performance enthusiasts, according to the Tire Rack online survey, the Pirelli P Zero Nero M+S was rated better in every category than the Goodyear Eagle RS-A. The Tire Rack survey is based on a huge database. The nearly 900 surveys for the P Zero Nero M+S alone represented 4.6 million miles of driving on that one tire. Of the 17 different Ultra-High Performance (UHP) tires, including the best from Michelin, Dunlop, Continental and BFGoodrich, the P Zero Nero M+S had the second highest ranking.

Among 20 High-Performance (HP), all-season tires sold by Tire Rack, including the best from Goodyear, Firestone, Michelin, Dunlop, BFGoodrich, Bridgestone and Pirelli, the Eagle RS-A was in the middle of the pack. The overall score from the Tire Rack surveys, with 10 being the best, is P Zero Nero M+S (8.4) and Eagle RS-A (5.8). Even taking the survey with a large grain of salt, it appears the P Zero Nero M+S is at least comparable and perhaps better than the RS-A in the opinion of enthusiast drivers.

The P Zero Nero M+S was in the top bracket (i.e., Superior rating) in all three “wet” categories, in the same top bracket in all three “dry” categories, and in the top bracket in both “comfort” categories. In all of the other areas, it was in the second highest bracket (i.e., Excellent rating). The P Zero Nero M+S had no ratings of Good, Fair or Unacceptable. The highest score (9.0) was for dry traction while the lowest score (6.2) was for deep snow traction. Lower ratings in the snow are common for all high and ultra-high performance tires.

17-inch Tire Comparison

Care must be used when comparing the new 17-inch police tires to the older 16-inch police tires. The sidewall profile of the 17-inch tire is much lower, which means two things. First, the response to steering input is faster, i.e., the change to a larger wheel, with no change whatsoever to the tire, will make the car more responsive during emergency lane changes and evasive, lane-to-lane maneuvers. Second, the footprint (contact patch) of the tire will change. All else equal, it will become a little shorter and a little wider, even if the actual surface area of the tread does not change.

At the request of Ford’s Ride & Handling engineers, the Los Angeles Sheriff’s Department tested a production prototype of the Pirelli P Zero Nero M+S. The tire survived the 32-lap, 64-mile pursuit course, something not all tires can do. However, the EVOC instructors subjectively felt the tire produced too much understeer and made the Ford CVPI difficult to handle at the limits of adhesion. As such, they disqualified this production prototype.

Little known to most police fleet managers, a version of the retail Crown Victoria has been available since 2002 with 17-inch wheels, the Crown Victoria LX Sport. These Crown Sport sedans use a suspension already tuned to the responsiveness of the 17-inch wheel, a tuning that included different shock valving and power steering assist profiles. A 2003 version of this Crown Sport was used as our test bed for the Pirelli P Zero Nero M+S tires. We took off the Eagle RS-A tires to put on the P Zero Nero M+S tires.

In our testing of the P Zero Nero M+S, it was quickly obvious that the Pirelli was a more responsive tire than the same 17-inch Eagle RS-A. It had a quicker turn-in approaching turns and corners. Pirelli indicates this is due to the shoulder block design and the solid center rib. Ford engineers indicate this is due to a smaller belt angle on this Pirelli tire than the Goodyear RS-A. Regardless of the reason, the tire was more responsive in emergency lane changes (suddenly move over one lane, then immediately move back) and in evasive maneuvers (suddenly move over one lane and stay there). Again, this was in comparison to other 17-inch tires of police-level speed ratings, and not in comparison to less-responsive 16-inch tires.

While the narrower belt angle of the Pirelli tire makes it more responsive at highway speeds, Ford engineers don’t want the tire to be too responsive at top speeds. For this reason, they prefer a slightly slower responding tire on the Ford CVPI.

The P Zero Nero M+S also felt to have better dry traction, during both acceleration and cornering. Evidence of this is that the traction control feature on the Crown Sport did not seem to activate as frequently as with the Eagle RS-A. Road noise was about the same. The ride felt slightly better.

Driving the P Zero Nero M+S in early winter in the Midwest also gave us exposure to wet conditions, light snow, slush and deep snow. The P Zero Nero M+S appeared to have better traction than the Eagle RS-A under most adverse road conditions, especially in the rain. With the slush and light snow, the advantage was not as large. In heavy snow, there was no difference between the two tires.

Overall, the Pirelli P Zero Nero M+S appears at least equal to the Goodyear Eagle RS-A in areas that are important to police use. While the P Zero Nero M+S may be tweaked more specifically to police use, we did not find any reason to do so during our extended patrol evaluation, including frequent speeds up to 115 mph.

So far, we have put 7,500 miles on the Pirellis, and have rotated them once at 5,500 miles. Up to this point, the tread wear appears normal. Do not expect better tread wear than the Eagle RS-A, at least not much better. If you are getting 10K to 12K in patrol on the RS-A, figure on 14K to 16K with the P Zero Nero M+S. However, don’t be surprised with 12K to 14K miles either.

Bottom line...get a set of 17-inch Pirelli P Zero Nero M+S tires and have your EVOC instructors test them. Keep it an apples-to-apples test, i.e., keep it a 17-inch to 17-inch test, a Goodyear Eagle RS-A to Pirelli P Zero Nero M+S test.

The use of this Pirelli tire on the Ford CVPI is not really about handling performance; instead, it is all about fleet pricing and local availability. While your EVOC instructors are scrubbing off rubber, get with your purchasing folks. Check into the availability of V- and W-rated tires in the 17-inch size used by the 2006 Ford CVPI. Then check into the pricing, and set up a bid process based on whatever your municipality requires.

The LASD has recently announced plans to test a variety of Pirelli, General, Goodyear and Continental 17-inch tires. Likewise, the California Highway Patrol has announced plans to test a variety of Firestone, Continental and Cooper tires.

NIJ Tire Tests

In the past, many police fleets have relied upon the NIJ to test and compare police-oriented tires. All of the tire information currently available from them is now obsolete, period. Totally new makes, models and rim sizes are in patrol use today that simply did not exist five years ago. In fact, not a single tire used today has been tested by the NIJ.

The NIJ's NLECTC last tested tires in July 2001, almost five years ago. At that time, the "Plus" version of the Goodyear Eagle RS-A did not exist. (This "Plus" version has an aramid belt in lieu of a nylon belt). Since that NLECTC test, 17-inch wheels have been installed on the Pirelli P6 Four Seasons tires. No Pirelli tire has ever been tested by the NLECTC.

Also since that 2001 test, the Dodge Charger and Magnum have been released. These come with 18-inch tires, a size never before tested by the NLECTC. The cars also come with Continental tires. Again, no Continental tire has ever been tested by the NLECTC. Eventually, hopefully, the NIJ will fund testing of modern police tires. After the recent vehicle platform changes and new introductions, the police vehicle market appears to be stable. The time to do the next round of tire tests is now.

Certified Police Tires

Pursuit-certified tires simply do not exist, i.e., there is no such thing as a true police tire. They existed in the 1950s and 1960s with names like Pursuit or Police Special or 125 (as in mph) embossed in the sidewall, but they don't exist today. The only certification of any kind that any tire manufacturer will supply is a speed-rating.

It is true that some tires have been designed with police input. The Eagle RS-A Plus on the Ford CVPI, the particular size of Pirelli P6 Four Seasons on the Impala, the Continental ContiProContact on the Charger/Magnum, and the General AmeriTrac on the Tahoe all come to mind. In each case, however these tires got little tweaks to an already existing tire... a subtle compound change, a slight tread pattern change or the addition of a belt. These are not clean-sheet designs specific for police use. Instead, these tires meet the specs for a particular speed-rating. The speed-rating tells all.

Ed Sanow is the Editorial Director for Police Fleet Manager, Law and Order, and Tactical Response. He can be reached at esanow@hendonpub.com.

Published in Police Fleet Manager, Mar/Apr 2006

Rating : 10.0


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