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COVER Michigan State Police Tire Tests the Goodyear turned in slightly better lap times. However, the big deal was the tire wear. No one is saying the tire wear dur- ing this kind of abusive track testing is comparable to the tire wear under nor- mal patrol conditions. However, it may be worth noting that the Goodyear had much less wear during the various test stages than the Firestone, like half the wear. S The Nitto NT850 had the shortest dry asphalt and wet Jennite braking distances on the new Chevy Caprice. Nokian – More Than Snow Nokian is better known by fleet managers in the snowy, northern states and in Can- ada than the southern part of the U.S. In snowy regions, Nokian is downright fa- mous for their Hakkapeliitta winter tires. Nokian tires hold the world's top speed record on ice. The best kept secret is that Nokian also makes All-Season tires – they list them as "summer" tires. Even to fleet managers familiar with Nokian winter tires, it may come as a surprise that their "summer" tires were so competitive during the MSP tests. On both the Impala and the Caprice, the new Nokians out-performed the new Good- years in four out of six categories. On the Ford CVPI, it was an even split. One of the great outcomes of the 2011 MSP/NIJ tire testing is to give well de- served exposure to the Nokian brand of tires. The tire experts in Finland clearly do summer tires as well as they do winter tires. Firestone Versus Goodyear The big showdown, of course, was Fires- tone versus Goodyear. Direct, heads-up, X The MSP did two versions of wet testing – wet braking from 35 mph on a Jennite surface, and wet braking while turning on asphalt. 26 LAW and ORDER I May 2012 26 LAW and ORDER I May 2012 no-holds-barred comparisons are pos- sible from averaging the results from the Charger and the Ford CVPI. First of all, the Firestone Firehawk GT Pursuit and Goodyear Eagle RS-A are quite compa- rable. The Firestone has better dry brak- ing and better steady-state dry cornering. The Firestone has a lot better wet braking under a variety of conditions. (Virtually every new tire test shows this same wet traction result.) On the other hand, during MSP testing, All that said, the Firestone versus Goodyear results from the Tahoe must be noted. The Firestone turned in better dry braking, static cornering and wet brak- ing, and much better wet braking while turning. The lap time advantage with the Goodyear tires hides the fact that the MSP were unable to complete the Good- year tests on the Tahoe due to excess tire wear. In comparison, the Firestone on the Tahoe had almost the least wear of the entire MSP test. Goodyear is obviously aggressively trying to resolve the wear issue. New Versus Worn The MSP took an entirely new and novel direction with their 2011 tire testing. They tested the new, properly scrubbed- in tires, and then repeated all of the tests with 100 miles of track testing on the tires. In almost all cases, the tires after 100 miles were not half-worn. In fact, in 13 cases out of 17, the tires were less than 70 percent worn (average of four tires) after complet- ing the entire series of tests. Of course, the testing on four of the tires was halted by