Improvements to the Family-Friendly Tires
As Cooper Tires celebrates its 100th anniversary, this year also marks the introduction of the new Cooper CS5 Grand Touring and Ultra Touring tires — claimed to be the most important tires in the company’s history. The new CS5 effectively replaces the company’s popular CS4 tire. With fitments for everything from minivans and SUVs to coupes and sedans, Cooper says they have a tire to fit most drivers’ needs. We headed to Cooper’s 1000-acre test facility outside of San Antonio to evaluate the tire’s capabilities.
While many competitors market their tires to the high-performance crowd, Cooper is targeting the everyday driver who wants a quality tire for their family vehicles. With that in mind, the tire maker wants to prove that its CS5 Grand Touring and CS5 Ultra Touring tires can handle extreme driving when necessary, such as during emergency maneuvers in wet and dry environments.
We tested the Cooper CS5 Grand Touring and Ultra Touring tires back-to-back against a set of popular competitor tires mounted on identical cars on wet and dry surfaces. After experiencing a competitor tire, we immediately jumped into a second car fitted with a set of Cooper CS5 tires. Once we finished testing, we also got to ride along with Indy Car legend Johnny Unser in a 2014 Chevrolet Corvette Stingray Z51 shod with a set of high-performance Cooper Zeon RS3-A tires.
First up, we drove a base 2014 Ford Mustang coupe fitted with Hankook Optimo H727 touring tires before experiencing a set of Cooper CS5 Grand Touring tires. Both tires are T-rated (maximum speed of 118 mph) and in the base Mustang’s stock 215/65TR17 size.
Hankook markets the Optimo H727 as a standard all-season touring tires with applications to fit coupes and sedans as well as minivans and crossovers. The tires are said to offer a comfortable ride, low noise, a long tread life, and all-season traction including in light snow.
The Cooper CS5 Grand Touring and Ultra Touring tires contain four times as much silica compound than the CS4 tires they replace. The increase of silica improves wet handling and braking performance, while helping improve fuel economy by reducing rolling resistance. Cooper also gave the new CS5 tires “3D Micro-Gauge” siping the entire (2/32) thread depth, which helps maintain performance throughout the life of the tire. The 3D Micro-Gauge sipes interlock with the adjacent sipes to maximize surface contact.
Our testing began at Cooper’s 14-acre wet skidpad (essentially a large, flat piece of asphalt covered by a thin sheet of recirculating water) before heading over to the dry auto cross. We rode shotgun with one of Cooper’s testers to get familiar with the wet course before hopping into the driver’s seat of a Mustang fitted with Hankook tires. Despite being warned about the tight left-hander coming off the long straight before beginning the next lap, I did a 720-degree spin at the end of my first lap — surprisingly, missing every cone along the way. Once the Mustang was pointed straight, I finished the last two laps with a bit more caution. Next, I stepped inside a Mustang shod with a set of Cooper CS5 Grand Touring tires.
Immediately, the Cooper tires provided a noticeably higher threshold of grip on the wet course. I was able to lap the autocross quicker on my first lap than with the Hankooks, including the last corner at which I had spun out. Where the Hankook tires gave out without warning, the CS5 Grand Touring tires had a higher wet road-holding limit and were much more progressive and communicative as they began to lose grip. While most people wouldn’t drive the speeds we did on a wet and curvy course, the test showed how well the tires may handle in an emergency maneuver on a rain-slicked road.
Next, we headed over to the dry autocross where we again tested the Hankook tires before testing the new Cooper CS5. The story was much the same on the dry surface. While I didn’t repeat my 720-degree spin with the Hankook Optimo H727 touring tires, I was able to do a bit more than a 360-degree spin on the dry tarmac. Fitted with the CS5 Grand Touring tires, the Mustang was able to carry a higher speed through the corners with more driver confidence.
After lunch, we finally got to try out a pair of BMW 328i sedans fitted with the higher performing Pirelli Cinturato P7 and Cooper CS5 Ultra Touring tires — both in the Bimmer’s stock 225/50VR17 size. Both tires are V-rated tires and capable of 149 mph.
Pirelli markets the Cinturato P7 as an all-season Grand Touring tire for touring and luxury cars. With low oil and high silica content, the lightweight tires offer low noise and long wear with good traction and braking in light snow.
This time our testing began on the dry track. Though not an apples-to-apples comparison, the Cinturato P7 tires mounted on the BMW 328i outpaced the Mustang fitted with the CS5 Grand Touring tires around the dry course. The V-rated Pirelli rubber was more communicative with improved handling over the T-rated Cooper tires. Most important, when the Pirelli tires did give out, the 328i only slid rather than spin out as it did with the Hankook tires. Again not an apples-to-apples comparison as the real comparison is against the BMW shod with the comparable CS5 Ultra Touring tires.
As impressive as the Pirelli tires were on the BMW, the Cooper CS5 Ultra Touring tires mounted on an identical 328i returned even higher performance, due to a combination of a higher grip level, more communication, and increased driver’s confidence. The fastest laps were attained in the BMW 328i with the V-rated Cooper CS5 Ultra Touring tires. I was able to keep the Cooper tires squealing on the edge of adhesion around most of the dry autocross including the long sweeper just before hard braking for a tight decreasing radius. The CS5 Ultra Touring tires also slowed down the BMW in time to hit the perfect apex each time.
We finished our tire testing where we began: at the wet autocross. Hopping back into the BMW with Pirelli tires, the story was similar. Where the Cinturato P7 tires provided better grip in the wet than the Optimo H727 and CS5 Grand Touring tires, the CS5 Ultra Touring tires returned the most confident laps. With the Pirelli tires, the BMW handled well in the wet with only the most evasive maneuvers causing us to slide off course. The Cooper tires were easier to drive at the limit without going past it even on the wet track.
The best lap times were set with the Cooper tires on the wet or dry courses; however, there was a more noticeable difference between the T-rated Hankook Optimo H727 and Cooper CS5 Grand Touring tires than the V-rated Pirelli Cinturato P7 and Cooper CS5 Ultra Touring tires.
Once our testing session was complete, Unser drove us around in the 2014 Chevrolet Corvette Stingray Z51 shod with a set of high-performance Cooper Zeon RS3-A tires. He took us around Cooper’s slalom/traction pad at high speeds with the Zeon tires right on the edge of adhesion. Unser didn’t take it easy on the Stingray as the transmission temperature gauge began to rise above safe levels.
Cooper notes that the new CS5 Grand Touring and Ultra Touring tires have new and potentially innovative features such as the above-mentioned coupled silica compound and 3D Micro-Gauge siping as well as a Wear Square visual indicator, StabilEdge technology, asymmetrical tread pattern, and durable uniform construction.
The Wear Square, located on the inner and outer edge of the tread, slowly wears down to let owners know how much tread remains. When a full square is visible, the tire is considered new. As it wears, the Wear Square begins to change shape. A U shape indicates 75 percent tread life, while an L indicates 50 percent tread life. An I means there is only 25 percent tread left and finally an ! means it’s time to replace the tires. Non-uniform wear of the inner and outer wear squares can indicate an alignment issue.
StabilEdge technology consists of small bumps between the larger tire grooves that stabilize the grooves and keeps them open while driving. The benefit is to improve response and traction, according to Cooper. With the asymmetrical tread design, the new CS5 tires feature an outside tread designed for handling and cornering, while the inside tread is designed for wet grip and traction. Asymmetrical tires can also be rotated side to side.
While Cooper’s new CS5 Grand Touring and Ultra Touring tires proved to handle wet and dry tracks better than similar peers, Hankook and Pirelli as well as many other competitors are also updating their product lines. For now, the new Cooper CS5 dominated these tests. Just like with rival automakers, stiff competition will only push tire makers to keep improving their products.