Propickup Digital Magazine
Issue link: https://read.dmtmag.com/i/105105
LAP TIME Each tire was put to the test on the road course. Several off-camber downhill corners tested the adhesion limits of tire design as snowbanks threatened to suck in the Sierra on each lap. BLIZZK W965 ULTRA GRIP ICE LAP TIME NOKIAN HAKKA GOODYEAR SR-A 2:38 2:45 2:52 3:00 3:07 3:14 3:21 Average times for three back-to-back laps around the Winter Driving School's .9-mile road course gives a good indication of how each snow tire faired in real-world driving. "Snow traction is more pattern-oriented; whereas, ice traction is more tread-compoundoriented," he explains. "The typical all-season/ M&S-type tire design uses a harder tread compound to give more mileage [better tread wear] and fuel economy. From a compound standpoint, that is the wrong direction for ice." "The key factor to a good snow/ice tire is finding a rubber compound that adapts to the road surface and retains that flexibility overall going into lower, colder conditions," says Kuykendall. That's why purpose-built snow tires, which are designed to maximize grip in sub-freezing conditions on frozen surfaces, have such a huge performance and safety advantage over their warm weather counterparts. SUBJECTIVE SNOW HANDLING ON HAKKAS The real test of how well tire engineers have done their homework is compiling notes and data at the end of the day-long test session. Some of the results were expected, other's not. For example, our test drivers gave the Nokian Hakkapeliitta LT's mixed reviews. "It delivered quite good acceleration and braking," says Spitzner of the straight-line performance. "But they were a little disappointing on the road course. "What I was least comfortable with in the lapping session," Spitzner continues, "is while I could generate a surprisingly decent lap time with it, in order to do so, I had to take it out of its comfort zone. I had to really drive it hard. And, it was hairy on the edge. Still, the Nokian's lap times were close to the best times laid down by the WRTs." UNDERSTEER 4 OVERALL 3 TRAILING THROTTLE OVERSTEER 2 1 0 BRAKING STEERING RESPONSE -1 -2 -3 -4 WORSE ACCELERATION BETTER RECOVERY Our test engineer had similar observations, noting "Having done some things with Nokian's Hakkapeliitta tires in the past, I was a little disappointed. They hook up well. They stop pretty well," says Kuykendall, "but the Hakkas didn't throw out the big numbers – or this case the small numbers – on the braking side, that I expected." ULTRA GRIP What surprised everyone was Goodyear's WRT snow tires out-accelerated and out-stopped the Nokians and consistently put down slightly quicker lap times on the road course. "The Goodyears accelerate surprisingly well, and of all three of the test tires, the Ultra Grip Ice WRTs were the most linear," Spitzner says. Kuykendall shares the praise on the Ultra Grip Ice WRTs adding, "The Ultra Grip is probably the number two tire in the group, in terms of numbers, braking numbers particularly. Pretty solid; one of the better LT [snow] tires I've been on." The WRTs averaged about 10 seconds quicker laps around the nearly mile-long track than the stock tires. Goodyear's snow tire out-accelerated the SR-As by nearly 20 feet and out-braked them by half-a truck length. The difference between the WRTS and the Hakkas was much closer, with the Goodyears SR-A ULTRA GRIP ICE CORNERING 56 PROPICKUP Buyer's Guide 2012 OVERSTEER FEEDBACK LINEARITY W965 NOKIAN 0 = Control 1 = Perceptible by professional driver 2 = Perceptible by enthusiast driver 3= Perceptible by average driver