They also were quite soft in the days of yore because the wheel size allowed for a tall sidewall and it could help cushion the load. However, that soft sidewall would not offer much stability at speed, and a change was needed as the cars got faster. By the late seventies, the radial tire, which used directional carcass piles to keep the sidewalls stiffer and would keep the footprint more consistent under pressure changes, had entered the scene.
Racing tires have to remain within a fairly narrow temperature window to work well, if at all. In fact, a cold racing tire has very little ability to generate traction, and can hydroplane quite easily. Road tires are subject to a much different set of criteria, have to be much more usable and are more compromised. Sport-oriented road tires provide some of the benefits of a racing tire with fewer drawbacks. The road tire will have to function in a variety of circumstances, and offer the user a little more feedback and warning before losing traction completely.
Therefore, the tread blocks flex slightly to give the driver a sense of when the tires are about to let go at the expense of overall grip.
Additionally, to be road legal and have the appropriate DOT rating, a minimum of two grooves are necessary. The compounds used to make these tires are designed for performance first and foremost, but must still last a reasonably long period of time.
Sports tires last a good thousand miles, which if used on the track can translate to a season of races with a careful approach. For the amateur of reasonable means, the level of grip offered by sports tires is wonderful value for the money. Notify me of follow-up comments by email.
Notify me of new posts by email. This site uses Akismet to reduce spam. Learn how your comment data is processed. Table of Contents. Ordinary car tier. Section width is the millimeters.
Aspect ratio is the 45—it means the tire's sidewall is nominally 45 percent as tall as the tread is wide.
Speed rating is a letter preceded by a number: An example "88Y. Again, this is a safe estimate. It does not mean a Z-rated tire will blow at Indeed, it may survive mph. Now that you know that, forget about it for the purpose of finding a grippy tire. Here's what you should look at:.
We know you need your tires to perform in a variety of conditions. However, some of the lesser-known brand names, especially those from South Korea, make some damn good tires. One lesser-known Japanese maker produced a tire that handed it to the big names on a damp track and matched them in the dry. I've also tested a Chinese-branded tire I'd never heard of before or since that matched the majors.
Going this route is a bit like investing in an unknown company: Use money you don't mind losing. Everything else being equal, the tallest, widest tire will put the most rubber on the ground. But if this is what you're looking for, you might not find it in tire company materials, which publish "nominal" sizes and diameters.
The tire industry association allows tires to fit within a size window, and then publishes the "theoretical size that may vary from the actual size. Performance tires are almost always in the upper corner of the permitted window, near the limit of what the tire governing body allows. To find the performance tire you want—the one that nudges right up against the upper limit of what your car can use—you might just have to get out your old-fashioned tape measure. You may have to call the tire company to confirm what's the best tire for your very specific need.
Find a general number and ask for product marketing. The poor guy probably used to be a test driver and would love to talk fast driving. Also, check out the customer reviews on the websites of the big Internet tire sellers—but be wary of what you read. This is a good place to find useful information from people solving the same problem, but it can also host a lot of misinformation from buyers who aren't experts. In our continuing example, the Michelin Pilot Sports intended for the Viper that I put on the Mustang were radically different from those designed for a Porsche Coupe, and those had some notable differences from those intended for a Chevrolet Corvette.
You'll see this when one tire size is listed two or three times, with different multiple part numbers in tire company specs.
While the Viper owner may praise the tire in his comments for its extreme grip, the Corvette driver may be upset because his Pilot Sports lasted "only" 30, miles. There's nothing like the thrill of the open road. It's unlikely that most drivers beyond those who hold or have held a racing license have the ability to take full advantage of even max-performance-summer tires, much less extreme-performance-summer rubber.
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