Continental have launched the successor to the award winning Eco Contact 3, the Continental ContiEcoContact 5.

With fuel prices ever rising, ultra low rolling resistance tires are a hot topic. The tire accounts for approximately 20% of the total fuel consumption of the car, and just a 10% reduction in rolling resistance can reduce total fuel consumption by 1.6%.

Traditionally ultra low rolling resistance tires are a compromise during development, with low rolling resistance balancing wet performance. As you decrease rolling resistance you also decrease the wet grip, or the safety of the tire, while increasing the wet performance leaves the tire requiring more energy to rotate, using more fuel.

New Development

During development of the Eco Contact 5 Continental set its engineers the ambitious target of reducing the rolling resistance AND improving the wet performance of the benchmark Eco Contact 3. To achieve this Continental worked on “modular zone technologies”, which splits the tire into 4 different zones.

• The grip zone: This is the tread and tread pattern, responsible for up to 50% of the rolling resistance
• Load zone: This is the structure under the the grip zone, responsible for around 10% of rolling resistance
• Flexing Zone: The sidewall of the tire, which contributes around 20% of the rolling resistance
• Rigid Zone: This is the area the tire meets the rim and includes the rimstrip and bead. The rigid zone adds around 20% to the rolling resistance of the tire.

By analysing each area of the separately Continental managed to bring efficiencies without sacrificing wet performance. The result? When compared to the Eco Contact 3 the new Eco Contact 5 has a very impressive 20% reduced rolling resistance, 10% better wet braking, 7% better handling and 12% longer tread life. Thanks to these reductions in rolling resistance, a car fitted with the new ContiEcoContact 5 tires will use around 3% less fuel than the same vehicle equipped with standard tires.

The Driving Experience

To help us evaluate the new Eco Contact 5 Continental provided us 2 challenges with 3 different tires. The first two tires comprised of the outgoing Conti Eco Contact 3, and its replacement the Eco Contact 5. The 3rd tire was called PrototypE, which is a development tire with an extremely low rolling resistance.

The challenges were designed to highlight the compromise of wet grip vs rolling resistance. During the first challenge we were instructed to drive identical Golfs fitted with each tire around a mountain circuit at a predetermined speed which had electronics developed in conjunction with Bosch to measure the precise amount of fuel used.

The second challenge used identical BMW 120i’s on a wet handling circuit and measured the wet braking performance and lap time of the 3 tires.

Subjectively there was little to take from the eco-run challenge, other than the prototype tire had a notably lower rolling resistance when coasting off throttle, and the Eco Contact 5 was a little quieter than the Eco Contact 3. The fuel consumption was reflected in the data at the end of the series of tests, with the prototype average 49.6 mpg compared to the Eco Contact 5s 46.5 mpg and the Eco Contact 3s 44.2 mpg.

The wet handling circuit offered a much better chance to get a feel for the tires. On leaving the pits the tires felt fairly similar, but as soon as reached turn one it was clear the Eco Contact 5 offered far more grip than the Eco Contact 3 and showed little signs of the understeer the older tire had. While the prototype offered the lowest rolling resistance, the resulting decreased wet performance was huge, with the car feeling extremely nervous and ended up over 6 seconds a lap slower than the Eco Contact 5 over just a 51 second lap! The out going Eco Contact 3 finished nearly 2 seconds behind the new Eco Contact 5, but was a much less stable lap.

During wet braking the Eco Contact 5 again led the way, on average offering 9.7 m/s2 deceleration compared to the Eco Contact 3s 9.1m/s2 and the PrototypE lagging at 7.4m/s2.

Above: was the result of our MPG vs wet performance data, which shows the Eco Contact 5 (orange) beating the Eco Contact 3 (green) in both wet performance and fuel consumption. While the PrototypE (blue) has the lowest fuel consumption, it also has the lowest wet grip.
Below: The wet lap times and wet braking performance of the 3 tires

Is now the time of ultra low rolling resistance tires?

While there will be a compromise between rolling resistance and wet grip for the foreseeable future, Continental has proven it is possible to produce a tire which offers better wet grip AND a lower level of rolling resistance to its predecessor.

Until a magazine tests a new Eco tire like the Continental Eco Contact 5 against a previous generation stardard tire like the Bridgestone Turenza TR300 it is impossible to say for sure, but on evidence of the Eco Contact 5 launch 2011 will bring ultra low rolling resistance tires to the forefront of the traditional tire market.

Size range (at time of launch)
70 Series:
165/70 R 14 T

60 Series:
185/60 R 15 H XL
195/60 R 15 H
205/60 R 16 W XL

55 Series:
215/55 R 16 W XL
225/55 R 16 Y XL