gavriil

Tire makers continue to improve performance tires but now they're avoiding the traditional downsides, such as poor handling in wet or snowy conditions, short tread life, and road noise.

Bridgestone unveiled its latest version of such a tire at the Jerez Formula One track in Spain: the Potenza S-03 Pole Position. It replaces Bridgestone's top street-performance tire since 1995, the S-02. The S-02 has been original equipment on the Aston Martin DB7 Vantage, Ferrari F360 Modena and F550 Maranello, Honda S2000, and Porsche Boxster, 911 and 911 Turbo. Bridgestone hasn't confirm-ed any OE fitments for the S-03 yet.

We sampled the S-03 at the F1 track, driving BMW, Audi and Mercedes street cars, rode with professional test drivers, and maneuvered an autocross course. John Rastetter, tire information director for the Tire Rack, who also attended the intro, described the S-03 as "a more civilized version of the S-02 and some other similar tires in the category."

Bridgestone also displayed a Ferrari F1 race car and one of its rain tires, unmounted. The tire was so light and soft that you could fold it up with your hands. The street tire isn't so soft and light, but uses some of the F1 rain tire's technology. Both the F1 and S-03 use H.E.S. (Hydro Evacuation Surface), which is sharkskin technology, also employed by NASA and in swimsuits that allow Olympic swimmers to glide through the water better. The water channels aren't the traditional smooth, straight design, but feature little protruding angles allowing for better water flow and drainage. Traditional straight channels, Bridgestone says, cause more turbulence (tiny, choppy waves) than the sharkskin-style channels.

Acronyms abound in today's tire technology. C.S.C. (Consistent Surface Contact) is also borrowed from the F1 program, and allows for more uniform contact pressure. The typical contact patch has the highest concentration of pressure on the edges, descending to almost none in the center. By changing the geometry of the tire, pressure is distributed more evenly. Throw in Super L.L. Carbon (longer carbon links to improve wear-resistance) and the diabolical-sounding Particle Z (provides better grip in the wet than silica) to the dark science of mixing tire compounds.

Bridgestone says a new tread-on-tread design (Dual Layer Tread II) provides more consistent performance in the wet as the tire wears. While the old S-02 used a dual-layer tread, the second layer of tread was not exposed until part of the outer tread layer wore away. On the S-03, the second, more gripping tread compound is exposed in the center of the tire when new, and that exposure is gradually widened from the center outward as the miles escalate.

The S-03's UTQG (Uniform Tire Quality Grading) treadwear rating is 220, vs. 140 for the old S-02. Rastetter estimates enthusiasts would get 25,000 to 30,000 miles out of the S-03. It will be available in May in 51 sizes, from 15- to 20-inch diameters.

Another new high-performance tire is the Pirelli P7, named after its progenitor from 1974. The original P7 evolved into the P700, P700Z and P7000, but, as a spokesman noted, Pirelli decided against calling its newest version the P70,000.

Pirelli says its engineers have strengthened the new P7's rigidity while making it lighter. A thinner but high-tensile steel belt and a nylon belt with "new Nylon 0" make the tire more rigid. That, along with a new rib and groove design and stiffer shoulders, enhances braking and cornering capability.

Like the Bridgestone S-03, the P7 features a footprint with more uniform contact pressure. Besides the perfor-mance benefits, it improves rolling resistance and provides 10 percent more even wear vs. the previous tire. With help from four longitudinal grooves, the new, wider contact patch also resists hydroplaning better.

P7s are scheduled to start arriving in the States soon, and Pirelli says the tire is in the OE approval process for makes such as Audi, BMW, Mercedes and Volvo.




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Gabriel
CL Type S

Tom2

Wow, thanks for that important message.

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dead CL-S and M3

buddha

that's some good info there. tlaked to some s2000 guys and they said the performance was not that much dfferent from the s-02. although for some reason there oem are wider than 225... they measured it and said that it was more like 255. go figure. i might give the p7 a try. depending on pirce of course.

EricL

Tires can have the same size, but very different footprints on the ground. Check out the Tread widths (not section widths) of various tires and you will see, that for a given size, they will have varying tread widths.

(I'm talking about the actual width of rubber making contact with the ground...)

Look around in www.tirerack.com and other sites if you car...



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Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines w/Brembos?
• Comptech headers & sways
• Silver AEM CAI
• 9 coats of Zaino magic

gavriil

That's right. Eric you are just getting better and better with all the science stuff. Very acurate and useful comments from you lately IMHO. Tell me, have you felt any difference from the lighter wheels on your car? As far as comfort or anything else?

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Gabriel
CL Type S

[This message has been edited by gavriil (edited 04-29-2001).]

Tom2

In addition to that, mounting identicle tires on different width rims can also "change" the actual width of the tire contacting the ground.



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dead CL-S and M3

EricL

Yes, the wheels make a big difference in:

1. Acceleration (sorry, only butt-o-meter)
2. unsprung weight.

This is just my opinion, so here goes:

I think I got more pick up from the wheels than from the headers and AEM (I can't prove it, it is just a "general" impression). When the wheels went on, it felt like I tossed out a couple of people.

The lighter wheels compared to the stock ones, felt very "light." When going over bumps and surface irregularities, the car feels very comfortable and smooth. The steering also feels lighter.

So, these are just my "impressions" and are NOT done in any controlled environment...



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Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines w/Brembos?
• Comptech headers & sways
• Silver AEM CAI
• 9 coats of Zaino magic

gavriil

I knew that would have made a big difference and that's why I asked. I do believe you on that. I have witnessed the opposite. I put on larger/heavier tires on a previous car and it felt like I added a person in my car permanently.


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Gabriel
CL Type S

BarryH

Just remember, that if you drive in snow be prepared to swap your high-performance tires out seasonally. My last car had Bridgestone Expedia 01's on it and was absolutely -terrifying- in the snow (they were excellent in the rain though). I'm not a big fan of the factory Michelin's but they're decent as a year-round tire and I’m too lazy to have to do the seasonal swap-out thing.

gto2050

Where can one find a "butt-o-meter" Eric?
Not sold in stores? Do I have to buy a Suzane Somers "Butt-o-matic" to get one?

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01 CL-S NightHawk Black/Ebony Bowling Ball Interior

mrtim

It's certainly true that "high-performance" usually means "not in the snow". My last car had Dunlop something-8000's and I think "terrifying" describes their snow performance as well.

That said I think some of these newer performance tires are *supposed* to be quite a bit better in the snow. The Pirelli P7000 comes in both a "Summer only" and "All season" models. Of course "better" in this context could well mean "terrible" instead of "terrifying".

EricL

When is is coming....

The "Butt-o-meter" and other products will be sold along with the:

Michelin/Exxon Valdez Pilots Super Slicks
Hot Air Intake
Depleted Uranium wheels
And our patented "Octane Killer"

I will need Soopa to add an X-rated section to fully describe ALL of the features of the new Butt-O-meter (Watch out GTECH, there is an new competitor in town).

Advertisement Teaser:

Folks, in the old days your ass was only good for a few things, now the "Butt-O-meter" is going to change all that. Mention the word butt and the thoughts of a nice tight ass or a big lard ass come to mind.

But, the butt-O-meter goes a step further. Now little asses, tight asses, saggy asses, all kind of asses are ready for a treat! The butt-O-meter will take that butt-hole and turn it into a precision driving instrument. (GTECH, we are gunning for you. In a few weeks you we will blow you away, like a fart in the wind.)

We would love to tell you more, but contractual obligations with a major proctologist spokesman and a well know automotive magazine prevent full disclosure at this time. We have an exclusive with them and will have to wait to fully describe the benefits of this wonderful device.



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Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines w/Brembos?
• Comptech headers & sways
• Silver AEM CAI
• 9 coats of Zaino magic

gavriil

Eric you missed this important thread I started:

http://www.acura-cl.com/ubb/Forum1/HTML/004678.html

What do you say?

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Gabriel
CL Type S