It was a sticky situation any red-blooded performance enthusiast would love to have been stuck with.
Hankook Tire America Corp. recently brought a handful of key tire dealers, wholesaler/distributors, accessory buyers and journalists to the heart of the Silicon Valley. The guests' job: hammer on two new Hankook ultra-high performance (UHP) tires, subjecting them to grueling acceleration, cornering and braking.
Tires that can survive such torture are a critical segment in today's marketplace, where no longer are just Vettes and Vipers fitted with premium, super-sticky low-profile rubber. Porsche Cayenne and Mercedes-Benz sport-utility vehicles have 'em. And the M in Infiniti's new M35 and M45 sports sedans could stand for ``massive,'' given that the standard tires are 18 inches in diameter and 245 mm wide.
The Holy Grail in UHP land is to have your cake (the traction of racing slicks) and eat it too (respectable tread life and safety). Yet owners of high-dollar performance vehicles are often stunned at discovering that, along with their vehicle's elevated status, come higher maintenance costs. Beyond wear, an irreparable road hazard can quickly deflate the most robust of checking accounts.
So do the new Hankook (stay with us now, their names would take up a good amount of sidewall space) Ventus S1 evo K107 and Ventus R-S2 Z212 represent double trouble for competitors in the hotly contested luxury performance and sport compact market?
``I like the K107s. Although we only got to drive them in the dry, they look like they're going to be good in everything. When you turned, they turned. They didn't slide,'' said Paul ``Skip'' Levengood Sr. of CJ's Tire & Automotive Service, a nine-store operation based in Birdsboro, Pa. CJ's also is the northeast distributor for Hankook's racing tires.
Mr. Levengood is qualified to evaluate performance tires. Not only is CJ's involved in local autocross racing, the Duryea Hill Climb and hot rod shows, the 57-year-old founder races his own race car at Sports Car Club of America regional events.
The K107s were demonstrated on BMW 3.0L Z4 sports cars. Additional Z4s, shod with Pirelli P Zero Rossos and Michelin Pilot Sport PS2s, were made available for comparison.
``The K107s are wonderful. I was shocked at how good the Hankooks were,'' Mr. Levengood told Tire Business. ``When I went from the Pirellis to the Hankooks, I turned in quicker and took out a couple of cones because you anticipated the slide for the drift and they didn't slide. They were much more predictable and much more precise.''
The K107 is slotted as Hankook's world-class ultra-high-performance tire for upscale vehicles, including sports cars like Porsches that have been extensively modified. How extreme? The K107 is available in a 25 aspect ratio, size 295/25ZR22. Ten other 17-, 18-, 19- and 22-inch sizes range from 225/45ZR17 to 265/30ZR22. The UTQG ratings are 280 AA A.
Engineers at Hankook's Technical Center set out to develop a tire that, according to the company, gives high traction, decent tread life and-for enhanced high speed cornering-minimal distortion of the tire footprint.
The key, Hankook said, was a combination of a next-generation silica compound that increases traction, extra-wide shoulder blocks and a stiff belt package that includes circumferential belt reinforcements. At the K107's outer edge, a wide, straight groove helps combat hydroplaning.
The circumferentially wrapped rayon construction makes the tire stiffer and more responsive, explained Ray Labuda, vice president of tire technology at Hankook's Akron R&D facility.
``We tried to limit the amount of changes in the tire's footprint at the extremes,'' he said. ``We used high-speed modeling and subtle differences in profile, design and construction, and that leads to better balance.''
Both new tires are optimized for dry performance and are ``summer'' tires vs. all-season.
The Z212 is an aggressively styled tire-what sport-compact consumers demand. But beyond the go-fast looks, Hankook engineers wanted a street-legal tire that delivered the progressive traction and communicative response of a racing tire. The technical team incorporated lessons learned from its racing-only RSS Z211, used by all competitors in the Hankook-sponsored United States Touring Car Championship series.
Hankook had Mitsubishi Eclipse convertibles on hand to demonstrate the new Z212. For comparison, other Eclipses were shod with competitors' tires: the Falken RT-615 and Kumho MX.
``The Ventus Z212 handled very well in both the normal and panic turn situations,'' said Ray Bartolai, of Kost Tire & Auto Service Centers, based in Clark Summit, Pa. ``I was impressed in the way that the tire stuck to the road. The newly designed outer tread area definitely was the reason for this. I would have liked to see its reaction in wet cornering.''
Mr. Bartolai said the 47-store family owned enterprise is looking forward to using the Z212s in original equipment replacement fitments. ``The Ventus Z212 was my choice, by far, as the better tire that we tested on the Eclipses. It's definitely another great addition to the Hankook Tire line.''
Despite its street friendly UTQG of 200 AA A, the Z212 can be a ``player'' on the track. In its debut at a recent Sport Car Club of America race in a class that stipulates street tires, a Subaru WRX-a near-iconic street/race/rally machine-wound up with a lead of just under one and a half seconds in SCCA's hotly contested STX class.
Available in 16 sizes ranging from 195/60R14 to 225/40ZR18, the Z212 features aspect ratios of 35, 40, 45, 50 and 55. Speed ratings are V, W and Y.