June 1, 2004
Vehicles Used
2003 BMW 330Ci
It wasn’t that long ago that only the most exotic sports cars were equipped with Max Performance Summer tires as Original Equipment. But today, as more vehicles are coming with these tires right from the factory, combined with an expansion of sizes beyond OE within many of the tire lines, the availability of these Max Performance tires is growing into sizes for more everyday vehicles. This allows drivers of sports cars, coupes and sedans to choose from a growing range of tire "personalities," each capable of delivering maximum performance.
One of the most recent OE-derived Max Performance Summer tires to be expanded into a range of replacement sizes is the Bridgestone Potenza RE050A. Versions of this tire have been fitted to cars from BMW, Ferrari and Mercedes-Benz. To get an understanding of how this tire performs in the real world on vehicles driven everyday, we conducted a Real World Road Ride and Performance Track Drive comparing the Bridgestone Potenza RE050A with the Goodyear Eagle F1 GS-D3 and the Michelin Pilot Sport PS2.
We used 2003 BMW 330Ci coupes, and installed 225/45R17 tires mounted on 17x8" wheels. This is a common "Plus Zero" tire and wheel package for the 330Ci coupe, and a popular "Plus One" package for standard 3 Series BMWs. Our evaluation used new, full tread depth tires.
We also included a fourth 2003 BMW 330Ci fitted with the Original Equipment 205/50R17 Goodyear Eagle RS-A High Performance All-Season tires mounted on factory 17x7.0" wheels. We have included this vehicle/tire combination in other tire evaluations, and have found it helpful to have an OE-equipped vehicle to evaluate the impact of installing the other products in the test.
Goodyear Eagle RS-A
The Goodyear Eagle RS-A is a High Performance All-Season tire produced with several speed ratings and in a wide variety of sizes. Its design is heavily influenced by its use as an Original Equipment tire by BMW, Volkswagen, General Motors, Chrysler and others. The Eagle RS-A features a subtle asymmetric tread design with larger tread elements in the outside shoulder intended to deliver more responsive handling, cornering, and steering. Smaller tread blocks on the inside shoulder combined with wide tread and lateral grooves are intended to enhance wet and snow traction.
Out on the road, the Eagle RS-A exhibited good road manners, providing levels of ride comfort and road noise that were appropriate for tires in the High Performance All-Season tire category. While delivering more ride and noise comfort than the Max Performance Summer tires in this evaluation, the Eagle RS-A could not match the road handling and crisp steering response of the other tires tested.
On the track in the dry, the Eagle RS-A offered handling that was appropriate for tires in the High Performance All-Season tire category. While the Eagle RS-A has proven it delivers respectable performance when compared to other tires in its category, it could not match the sure-footed feel or quick average lap times of the other three tires in this evaluation.
Under wet conditions, the Eagle RS-A High Performance All-Season tire proved to be at an even bigger disadvantage over the Max Performance tires in this test. It posted an average lap time 1.9 seconds behind the first-place Goodyear Eagle F1 GS-D3.
Bridgestone Potenza RE050A
The Potenza RE050A is a Max Performance Summer tire originally designed to complement the performance of the supercharged Mercedes-Benz S55 AMG sedan, the Enzo Ferrari Supercar (as a Scuderia version), and the BMW Z4 sports cars and 5-Series sedans (as a Runflat version). Since its introduction as Original Equipment on these performance vehicles, the Potenza RE050A line has been expanded to include more sizes, designed to provide good traction along with responsive and predictable dry and wet road handling for many of today’s sports cars, coupes and sport sedans.
The Potenza RE050A features a high grip tread compound molded into an asymmetric tread design, where a continuous center rib, large tread blocks and stable shoulder elements provide responsive handling, high-speed stability and traction on dry roads. Circumferential and lateral tread grooves are aimed to pump water out from under the tire’s footprint to minimize hydroplaning and aid wet traction. Internally, the Potenza RE050A features twin steel belts reinforced by spiral-wrapped nylon to stabilize the tread area and enhance handling, high-speed capability and ride quality while minimizing weight. The fabric cord body and hard rubber sidewall filler help blend ride quality with steering response and lateral stability.
During the Real World Road Ride on the roads and highways surrounding our headquarters, the Bridgestone Potenza RE050A displayed sporty road manners, feeling nimble and very responsive. The tradeoff was a ride that was somewhat firmer over the sharper bumps and expansion joints than the other Max Performance tires in the test. Noise level was not objectionable, and rated as appropriate for a tire in this category.
On our dry handling track, the crisp handling of the Potenza RE050A received good marks by our team, and felt responsive and easy to drive. The Potenza RE050A did not offer quite as much lateral grip around the skid pad as the other two Max Performance tires, however.
Under wet conditions, the Potenza RE050A again felt very responsive, and was easy to drive. It again did not have quite as much wet grip as the other two Max Performance tires in this test, finishing a close third for average overall lap time.
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 sporty. We were not able to evaluate long-term wear characteristics, or the potential some highly directional tires have to develop noise-generating, irregular wear. While the Eagle F1 GS-D3 generated somewhat more tread noise than the Original Equipment tire, it was not found to be objectionable by our team.
On the test track in the dry, the Eagle F1 GS-D3 was praised for its handling and overall grip around the skidpad. When driven at the limit, this tire provided a broad, comfortable window to work in, making it easy to drive aggressively. Steering response was good, but not quite as crisp as the other two Max Performance Summer tires in this test.
On the wet track, the Eagle F1 GS-D3 just edged out the Michelin Pilot Sport PS2 for the fastest average overall lap time, and scored well 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 resulting in 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 taut road feel and provided crisp steering response. This 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 delivered a strong performance, 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. The Pilot Sport PS2 felt predictable, and easy to control at the limit.
In the wet, the Pilot Sport PS2 also proved to be fast, nearly matching 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 provided driver confidence in the fast transitions of the slalom and hard 90-degree corners around the track.