To introduce the Scorpion ATR, Pirelli had gone out of its way to give the media a chance to experience the virtues of this newly designed tire, constructing an "off-road course" on a flat dirt field at the Las Vegas Speedway for two Jeep Unlimiteds to conquer. Instructors in the passenger seats guided the magazine writers through the Case tractor-induced hazards, proving for all practical purposes that an Unlimited isn't, at least in the suspension articulation department, and that the new tire was holding air.
Journalists were then treated to a trail ride in the nearby Nevada desert, in 4x4s ranging from capable stock Dodge Durangos to a Hummer with 22-inch wheels. Thus we were able to learn that the ATR is quiet on pavement and that a stock Grand Cherokee can go places that the Pirelli officials didn't want it to be, despite being saddled with a single-speed transfer case. Still, it didn't really educate us all that much on the tire's capabilities. Especially since we weren't allowed to air down-which was probably just as well since there were no means to air back up.
Now, how was anyone supposed to know what the Scorpion ATR could accomplish based on this? Had we penned our impressions at this point, we could certainly conclude that the Pirelli Scorpion ATR was round, black, quiet on the highway, and still held air. Also, that the ATR seemed to work fine on dirt roads and mild trails. We'd expect that much from any modern, non-mud tire.
Available in 31 sizes at this...
Available in 31 sizes at this writing, the Scorpion ATR comes from a smallish LT215/75R15 to a "why?" LT325/45, in 15-, 16-, 17-, 18-, and (gulp) 20-, 22- and 24-inch rim sizes. For 'wheeling on more than mall parking lots, the LT325/65R18 (34.6 inches tall) is probably the biggest practical size. This 265/65R17 mounted on an American Racing 17x8 wheel provided very good handling on pavement, plus the ability to traverse most trails where our stock vehicles could go.
With a good driver (or not,...
With a good driver (or not, this time it was Rick Pw), but without the benefit of low range, this ATR-shod Grand Cherokee went places that the Pirelli people said it couldn't. If anything held the vehicle back on the Nevada desert trails, it was a lack of ground clearance and the aforementioned lack of gearing ... not the tires.
As with most modern tread...
As with most modern tread designs, this pattern didn't just happen. Pirelli spent many hours designing and testing before finally releasing the tire to the public. Without going into the finer details of the design, notice that there's a semi-continuous center rib for stability, good water dissipation through the swoopy grooves next to it, and decent-sized shoulder lugs for traction in the dirt. Plentiful siping is always a good sign too.
Pirelli's hired hands insisted...
Pirelli's hired hands insisted that we use four-wheel drive on this tractorized course-for insurance reasons. We disobeyed and used two-wheel drive. Sure enough, the Scorpion ATR went the distance without a problem. The tires worked, but it did require some left-foot braking to overcome the limited suspension travel of the Unlimited's suspension.