When Cooper set out to make the CS5 Touring line of car tires, it didn’t want to create just another tire. It wanted to celebrate what it has built and grown into over the last 100 years. It wanted to create one of its best tires ever. More than that, the company wanted to prove that it could create tires that are world-beating, and every bit as impressive as those from companies like Michelin and Pirelli.
Cooper invited a collection of journalists including myself to come to its tire testing facility in Texas to give these tires a real test . We spent time doing laps in wet and dry to push these slabs of rubber to the breaking point. As there are two models in the lineup, Grand Touring and Ultra Touring, Cooper was even kind enough to round up cars wearing competitor rubber from Pirelli and Hankook to prove just how good the new tire really was.
Read on to learn more about the Cooper Tire CS5.
The Ultra Touring tire is the higher-end of the two tires in the CS5 lineup. It is designed as a premium touring tire for owners of cars that wear badges like BMW, Audi, and Cadillac.
The Ultra Touring comes in the traditional V and H speed ratings, good for 149 and 130 mph respectively. Each one of these comes with a 60,000-mile treadwear warranty. Cooper also produces the Ultra Touring in a less common W rated model that is good to nearly 170 mph. The higher performance of the W comes with a slightly lower treadwear warranty of 50k miles.
The competition for the Ultra Touring tire was the Pirelli P7 Cinturato. Compared to the CS5, it will cost you about $100 more per car or so for a new set of the Pirelli’s versus the Coopers. Does that $100 buy you any more performance?
Well we started on the dry track in a pair of BMWs. They were 328i models to be exact.
It can be very hard to describe the subjective feel of a tire, especially in writing, so let us use some math and science. One a closed circuit loop a good tire will allow you to push the car with confidence. Lap times should be consistent and quick. A poor tire will demonstrate unstable grip levels with varied heat loads, cause you to trust the car less, and in the end it will affect your lap times.
Since all twelve of us had lap times recorded, I had plenty of data to pour over. In the dry, the lap times were close with Cooper coming out ahead by just under 2 percent (1.842%). That is a nearly pointless performance gain, but we are on dry pavement in cars that are far from the most powerful. Neither set of tires felt like they were being pushed to their extreme. The real win for Cooper here is that even though it was only able to barely edge out the Pirelli tire in dry lap times, a quick internet search will show that the CS5 is cheaper. With an average price delta of $35, you are looking at saving $140 on a full set. So slightly faster, but a lot cheaper.
That price difference would be enough to make most people decide on the Cooper CS5, but if you want some more evidence of the incredible engineering that went into this ring of rubber, let us look at wet laps.
It could make the difference between completing a panic stop and crashing into the car in front of you
Cooper spent a LOT of time on wet weather performance for the CS5. The company felt that based on the safety aspect and the performance potential of the types of cars these tires are used on, maximizing wet-weather traction and grip was crucial. Our wet laps were not only longer than the dry laps, but featured more corners with sections that were far more technical than the dry circuit.
When the dust settled, there was a clearer picture of performance differences. When the road gets slippery, the Cooper CS5 increases its leading gap to 2.5-percent (2.474%). Again, it is far from a huge gain, but it could make the difference between completing a panic stop and crashing into the car in front of you. When you consider the minimum level of performance required for a tire in the class, Cooper providing a cheaper tire that works better is rather remarkable.
Not bad for a tire competing with the official supplier of Formula One rubber, eh.
For testing the more mainstream Grand Touring tire line, Cooper slapped us in a pair of V6-powered Mustangs; one car wore shoes from Cooper, the other was wearing Hankook Optimo H727s. When pitted against the Pirellis, the CS5 did well but not exceptionally. That change very quickly when looking at the more mainstream tires we have here.
This tire is a more conservative tire with a speed rating of T, and it has a treadwear warranty of 80,000 miles.
When it comes to tire sales, this class of tire is one of the largest in the business. There are far more family sedans and lower-tier performance cars running the road than premium level Audis and BMWs. If Cooper really wants the CS5 line to succeed, it needs to get this tire perfect.
Just like the previous tires, we started the tests out on the dry pavement. After nearly 50 laps between the 12 of us, we had a nice collection of numbers. Final tally comes to Cooper holding a 4-percent (3.942%) performance lead. With a more mainstream tire, Cooper has managed to outperform the Hankooks in the dry by a greater margin than it could accomplish in the wet before.
From the driver’s seat you could feel the difference too. With the Hankooks, I kept out-driving the tires. I would plow wide in tight corners, the car was wobbly under heavy brakes, and it was very unpredictable. Once I hopped into the car with the Cooper tires, I suddenly wished the Mustang had more power. I couldn’t go faster than the tires would handle. No matter how hard I pushed, the rubber obeyed.
With such an impressive showing, we were all excited to see just what this thing could do when it came to the wet.
Our excitement quickly turned to worry and concern as both cars felt dramatically worse on the wet. The Ultra Touring tire they put on the BMW never showed any major signs of understeer and provided great stopping power. The Mustangs felt wayward and frightening. But this is a test backed by numbers, not feelings, and those numbers told an incredibly interesting story.
When being flung around a sopping-wet track, the Mustang was more than 7-percent faster on Cooper rubber
While both Mustangs felt worse than both BMW’s it became very obvious which company was still making the better tires. They might not have felt as good, but the Cooper-equipped Mustangs were actually faster than the Pirelli-shod Bimmers. I am going to attribute the unstable feelings we all described to the Mustang’s overall wayward handling compared to the BMWs precision. Again, feelings are subjective, but numbers don’t lie.
What did those numbers tell us in the end? When being flung around a sopping-wet track, the Mustang was more than 7-percent (7.335%) faster on Cooper rubber than Hankook. When making a panic stop from 60 mph on a wet highway, that could be a difference of 20 or more; far more than one entire car length.
Cooper doesn’t hold as much of a price advantage here though. From what I can find, the Hankook sells for almost the same price at most retailers.
How do they do it?
When it came to designing the CS5, Cooper spent tens of thousands of hours trying tread patterns, rubber compound compositions, and more. They put more than 1-million miles road testing them. Nothing short of perfection would be accepted.
Aside from the expected tire technologies like a silica-based compound and the asymmetrical tread design, Cooper added new features like the Wear Square, 3D Micro-Guage Siping and Stabiledge.
Stabiledge is a small knob of rubber that is positioned in the tire tread that helps prevent deformation of the tread pattern. When making an aggressive turn, the rubber of the tires moves and deforms, sometimes actually causing the tread blocks to close together. Without spacing between the tread blocks, you can’t evacuate water and wet weather performance suffers. Stabiledge keeps the tread separated so even during hard wet cornering, the tire is performing as it should.
The Wear Square is another great innovation that is particularly useful for buyers who are unfamiliar with tires and when to change them. As gear heads, we all understand that bald tires are bad, but take a look around the parking lot the next time you are the mall. Count how many cars have dangerously bald tires. The Wear Square is designed to help owners understand how much tread life their tires have left. For every 25-percent wear the tire has, the square loses one side. So at half-life, the tire shows only one-half of a square. It is simple to understand and effective. When the tire has reached the legal minimum tread depth of 2/32 the last line of the square turns into an “!”. To get a better idea of how it looks, check out this video. It is a little cheesy, but does a good job of explaining what the Wear Square looks like.
It is a brilliant design.
What’s the take-away?
Tires are boring, and buying tires sucks, but this should go to show that not all tires are created equal. To that end, trusting a tire based solely on brand name isn’t always the best option either. It may seem like a terrible way to spend a Saturday afternoon, but considering it can save you a lot of money, and maybe even save your life, doing a bit of tire research seems like a good idea.
As for me, I think you’ll see a Cooper logo on the tires of my Golf and my Porsche very soon.