The Discoverer STT Pro from Cooper Tires, which took around two years to develop, features 80% off-road and 20% on-road terrain capability. It’s designed to provide high levels of traction and toughness with decreased treadwear for the most challenging off-road conditions such as thick mud and rocky terrain.
Right: Produced in the USA, the tire is available worldwide
Pete McNally, general manager of Cooper Tire’s European Technical Centre in Melksham, UK, explains, “The mud flex design means that the tread blocks have mud release dimples and mud scoops. These help the tire move through thick mud without the tread pattern getting clogged up. Wide lateral grooves enhance the tire’s all-terrain capability. It also has specific elements designed into the tread to ensure stones don’t get trapped in the tread blocks.”
Cooper’s Armor-Tek3 construction technology adds strength to the sidewall and tread area in order to maximize impact resistance. A new silica-infused tread compound improves wet traction in day-to-day traffic and the tire has lower rolling resistance for improved fuel mileage.
In the development of the Discoverer STT Pro, engineers used finite element analysis modeling to fine tune the carcass and belts. Extensive testing was carried out at the Cooper Tire and Vehicle Test Center (CTVTC) in Pearsall, Texas, USA.
“We have a full 4×4 off-road circuit with a range of surfaces. Tests cover a range of disciplines including wet and dry handling and braking; ride quality and noise; loose surface track; boulder crawling; polished stone wet and mud tracks,” notes McNally.
Meanwhile, Cooper Tire Europe recently introduced the Cooper Zeon CS8 passenger car tire, which has an A rating for wet grip on the EU tire label.
“The CS8 is lighter than its predecessor. We focused on the wet grip while retaining competitive fuel economy grade and low noise by introducing dimples into the tread. The tire features highly-dispersed silica in functionalized SBR and Cooper’s new wear square visual indicator allows drivers to quickly see the approximate tread life remaining on the tires,” McNally says.
To achieve the A rating for wet grip, the tread pattern is designed with large circumferential grooves that clear water quickly and efficiently from the contact patch to reduce aquaplaning.
The tread pattern of the CS8 also features 3D sipes, which have interlocking three dimensional points inside the sipe. The 3D sipes provide the same benefits of a traditional sipe, including helping the tire warm up and providing enhanced wet grip. But they limit the amount of flex in the tread block which helps control the amount of heat generation in the dry and keeps the tread block stable.
During testing of the tire, former F1 driver David Coulthard was said to be an asset, providing the product development team with valuable feedback. Test locations included MIRA proving ground in the UK, Fontage in France and IDIADA proving ground in Spain.
Below: Tires are made at Cooper’s UK and Serbia factories and sold throughout the EMEA
December 18, 2015