GS-D3 vs PS2 [Archive]

Luke@tirerack

06-02-2004, 02:35 PM

The Potenza S-03 Pole Position Max Performance Summer tire brings Bridgestone’s F1 tire technology and design to the streets. The Potenza S-03 Pole Position features Bridgestone's UNI-T AQ II Technology that uses advanced compound and construction features to enhance and preserve wet traction through the tire's life.

The Potenza S-03 Pole Position molds Bridgestone’s second-generation dual layer tread compound into a directional tread design that features notched shoulders, large "High Nose" intermediate tread blocks (that are shaped like the side view of a "high nose" F1 car) and a continuous center rib to provide quick, dry road response and handling. The continuous center rib exposes a strip of the underlying second compound on day one to enhance wet traction, and also helps reduce noise while providing constant road contact to enhance straight-line stability. Slanted grooves help direct water through the tire to resist hydroplaning. Internally, the Potenza S-03 Pole Position features Bridgestone's Computer Optimized Component System which blends steel belts with spiral-wrapped Jointless Cap & Layer Construction to stabilize the tread area and enhance handling, high-speed capability and ride quality while minimizing weight.

Driving around our Real World Road loop, the Potenza S-03 Pole Position delivered crisp, sporty handling, along with reasonable ride quality, and moderate tread noise. The Potenza S-03 Pole Position was not as quiet as the Goodyear Eagle F1 GS-D3 and did not handle as crisply as the Michelin Pilot Sport PS2, however.

When pressed hard on our dry handling course, the Potenza S-03 Pole Position displayed the balanced performance that is a Bridgestone Potenza trademark. Good, solid performance along with the driver confidence that comes from a traction level that matches up with the level of initial steering response allowed the Potenza S-03 Pole Position to produce an average lap time just 0.23 seconds behind the first-place Michelin Pilot Sport PS2.

Under wet conditions, the Potenza S-03 Pole Position offered overall performance that was appropriate for Max Performance Summer tires, but could not match the grip or quick lap times of the other two Max Performance tires in this evaluation.

Note: Our evaluation used new, full tread depth tires, and we were not able to evaluate the wet performance during the second half of the tire’s life where the possible wet traction advantage of Bridgestone’s dual layer tread compound vs. other similarly worn tires might show itself.

Goodyear Eagle F1 GS-D3

The Eagle F1 GS-D3 Max Performance Summer tire was developed in Europe for driving enthusiasts around the world who want more performance from their factory stock or aftermarket tuned sports cars, sporty coupes and performance sedans.

On the outside, Eagle F1 GS-D3 tires feature Goodyear's AAtrax tread compound molded into a distinctive, highly directional tread design. The OneTRED design combines three distinct patterns in the tread design to enhance dry and wet performance. First, a solid and continuous center zone maintains constant road contact to enhance straight-line tracking and initial steering response. Next, sweeping intermediate ribs emulate racing slicks by delivering shoulder-to-shoulder tread contact to further enhance steering response and dry road cornering traction. The sweeping aquachannel grooves, which are three times longer than the tire's contact patch, angle forward and out to the edges of the tread to avoid trapping air and water to reduce noise while enhancing wet traction and hydroplaning resistance. Finally, the intermediate ribs flow into the shoulder area to form long, stable shoulder blocks to grip the road during cornering and help resist the wear associated with aggressive driving.

Internally, steel belts are reinforced with spirally wound nylon to distribute the vehicle's load across the tire's footprint to provide high-speed durability and uniform ride qualities. Slightly angled body ply construction with high ply turn-ups enhance steering precision and high-speed stability.

On the road, the Eagle F1 GS-D3 felt responsive and nimble. While not whisper-quiet, the Eagle F1 GS-D3 held a modest advantage in low road noise over the other two Max Performance Summer tires in this evaluation. We were not able to evaluate long-term wear characteristics, or the potential some highly directional tires have to develop noise-generating, irregular wear.

On the test track in the dry, the Eagle F1 GS-D3 was praised for its handling and overall grip around the skidpad. Steering response was good, but not quite as crisp as with the Pilot Sport PS2.

On the wet track, the Eagle F1 GS-D3 was rated highly by our team for cornering stability and predictability, providing confidence and plenty of traction in the higher speed corners. The aggressive, highly directional tread pattern was not challenged by the water level of our wet test, which is not designed to evaluate hydroplaning resistance.

Michelin Pilot Sport PS2

The Michelin Pilot Sport PS2 Max Performance Summer tire was initially developed for use as Original Equipment on some of the world's most prestigious sports cars and sports sedans by combining world-class wet and dry handling with confident and predictable cornering. Some of the first fitments include the BMW Alpina Z8, Chrysler Crossfire, McLaren SLR and Porsche GT2 and GT3 models.

The Pilot Sport PS2 tire features advances in performance, wear, durability, and comfort thanks to Michelin's patented C3M manufacturing technology, a highly advanced production process that allows for extremely precise placement of a wider variety of tire components than ever before. The Pilot Sport PS2 tread features two different rubber compounds across their treads. A hybrid silica/carbon black compound begins at the tire's outer shoulder and continues across the tread until it joins a high-silica compound that continues to the tire's inside shoulder. Each of these tread compounds is specifically formulated for its location to optimize dry and wet handling for crisp, predictable cornering and increased wear and high-speed durability. Additionally, these high grip tread compounds are molded into an asymmetric design with large outer shoulder blocks along with continuous intermediate and center ribs (similar to that of Michelin's Formula One tires) to enhance steering response and cornering stability. The tread design also features wide circumferential grooves and lateral notches that help channel water through the footprint to enhance wet road traction. On the inside, the tread design is supported by two, high-tensile, lightweight steel cord belts that are further reinforced by size-optimized, precisely placed, individual Aramid/nylon hybrid filaments. These Aramid/nylon hybrid filaments replace the old bands of nylon to bring the Pilot Sport PS2 to a new level of manufacturing and design-tuning precision. This precision allows the Pilot Sport PS2 to provide improved steering response and resistance to distortion while enhancing ride quality and high speed durability.

During the road portion of our evaluation, the Pilot Sport PS2 displayed impressive road manners. The taut feel received high marks for handling by providing crisp steering response, but did cause the Pilot Sport PS2 to feel just a little firmer than the other two Max Performance tires over the sharper bumps and expansion joints. On coarser concrete and asphalt surfaces, the Pilot Sport PS2 generated some additional tread noise, although our team did not find ride comfort and noise levels to be objectionable.

Out on the dry test track, the Pilot Sport PS2 was the clear winner, offering very good handling and turning the fastest average overall lap time of the test. Steering response was sharp without feeling nervous, and felt stable in the higher-speed, sweeping corners. Gone is the gentle understeer of the 1st generation Pilot Sport, giving way to a neutral balance that made the Pilot Sport PS2 predictable, and easy to control at the limit.

In the wet, the Pilot Sport PS2 also proved to be the fastest, edging out the Goodyear Eagle F1 GS-D3 for best average overall lap time. While the Eagle F1 GS-D3 felt slightly more stable around the fast, sweeping curve of the skidpad, the Pilot Sport PS2 offered moderately sharper steering response and good overall driver confidence in the fast transitions of the slalom and hard 90-degree corners around the track.