It's hard to believe all modern car and truck tires can trace their origins back to a day in 1888 when John Boyd Dunlop, a Scottish veterinarian, invented the first practical pneumatic tire upon seeing his child's discomfort while bicycle riding over cobblestone streets. His patent for an air-filled tire, although not the first example of a pneumatic tire, was commercially viable and paved the way (pardon the pun) for modern tires.
Over the years, tires have evolved from tubeless tires in 1903 (first mass-marketed on the '54 Packard), grooved tires in 1908, carbonized rubber in 1910, steel-belted radials in 1948 and a number of other small steps cumulatively leading to the tires we have today. In recent years, computer modeling has reduced the time needed to develop new tires by simulating how a tire reacts to the road under dynamic conditions, allowing a designer to go from concept to concrete without undue physical prototyping down dead-end roads.
Ultimately, these technologies are validated through the rigors of racing and the resulting transition to daily drivers. If you've been following DTM this past season, you may have noticed the yellow-emblazoned Dunlop SP Sport Maxx on the sides of each race car's tires. As with every tire manufacturer's ultra-high-performance contact patch, Dunlop has introduced a new acronym to summarize its advances. MRT (Multi Radius Tread) is the new technology designed to offer a bigger footprint to the ground under straight-ahead or cornering conditions. Although MRT is the word of the day, Dunlop's SP Sport Maxx is built on a foundation of five core technologies.
Most visible when viewing the Sport Maxx is its solid center rib, replete with Sport Maxx lettering. Not just a place to tack a logo, the center rib has repeatedly been demonstrated to provide a stable structure that allows for steering feedback and high-speed stability.
Moving outward from the center, the Sport Maxx features Dunlop's Twin Hydro-Paddle Directional Tread pattern. As its name implies, the hydro-paddles are designed to improve water draining and wet-weather performance by shoving water outward to the next groove between the five longitudinal ribs. Across the tread, the five-block arrangement reduces road noise and improves driver comfort.
A phrase without adequate explanation is Dunlop's Integral Rubber Matrix said to better disperse the compound for improved adherence resulting in excellent braking and acceleration.
Last, but certainly not least, is Dunlop's MRT. Over the years we have grown accustomed to viewing tires in a top-down (or bottom-up manner), but Dunlop has changed its design perspective to a front view; that is to look at the tire radius across the tread perpendicular to the direction of travel. In creating MRT, Dunlop engineers considered how the angle of a tread block confronts the roadway in a dynamic environment. As the tread block loads from the side and distorts, uneven surface pressure can result across the width of the tread. By presenting multiple radii across the tire, a larger contact patch will meet the road surface offering better grip.
Upon first drive, I almost put the car sideways exiting a curved bumpy off ramp. Upon inspecting the tires, I found that most had 40+ psi, which while below the maximum allowed pressure, isn't conducive to performance handling; a minor setback quickly remedied. Don't trust your wheel-and-tire shop to put the appropriate amount of air in. I can't attest to their wet-weather performance as it hasn't rained here in SoCal in a very long time.
After a few more days of driving, what was impressive was the reduced noise. After being scrubbed, the Sport Maxx tires continue to improve, and the ultimate judgment will be when they're off. Until then, give Sport Maxx a look-see, and if possible, try them out. For those of you who live where it rains, let me know how they turn out.