Speed Ratings:

Speed ratings indicate the safe top speed of a tire under perfect operating conditions.  These include optimum inflation, road surface and ambient temperatures.

Yes, V,W,Y and Z are a bit vague in their descriptions. However, for most performance cars any of these are perfectly sufficient.

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Tire Pressure:

Tire pressure is probably the most critical aspect of tire safety and failure.  Most often the failure mode is over heating caused by under inflation.

It is extremely important to remember that your recommended tire pressure is a 'cold' pressure; that is, it is the pressure in the tire when the vehicle has been parked for several hours and is not in the sun.  The maximum recommended tire pressure is written on the sidewall of each tire.  Having said that, there are times when you may want to alter your tire pressures.  For liability reasons, we will not address these at all.

There are factors that cause your tire pressures to change; some of these we should address.  This first is ambient temperature and the second is load.

Most tires are filled with air, which is a gas that reacts to temperature changes.  For the most part, your tire pressure will increase / decrease about 1 psi per 10 degrees of temperature.  Other factors often forgotten are the road temperature, vehicle speed and load on the tire.  Drive your car on a black, asphalt road in the summer and the road is often well over 110 degrees on a sunny 85 - 90 degree day.  Increasing your vehicle speed increases the friction between the tire and the road; this also increases the tire pressure.  A fully loaded vehicle also increases the tire's temperature as it increases the friction between the tire and the road.  It is not uncommon to see pressure increases of 5 - 7 psi.

When checking the pressure of your tires, it is best to develop a routine.  That is, try to check them in a shaded area at the same time be it morning of evening and make sure that your check the pressure when the tires are 'cold'.  We try to check our tire pressure at least once a month and always before a highway trip or performance driving.

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Contact Patch:

Contact patch is probably the most misunderstood aspect of a tires' function. Basically it is the tires' foot print; or in the terms of an often-used phrase, it is where the rubber meets the road.

Contact patch is directly related to tire size and shape. Tires with high aspect ration have long, narrow contact patches and low profile tires have wide, short contact patches. In the latter case, the wide patch combined with the short, slightly flexing sidewall; is responsible for superior handling, stability and traction. On wet roads, these same qualities may become a 'negative', as a wide tire tends to hydroplane much faster then a narrow tire. That is, they may tend to ride 'on top' of the water and not the road. This is often a disaster waiting to happen. Most tire companies take great pains to try to engineer water dispersing tread patterns into their low profile, performance tires.

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Vibration Problems:

In new tires, most vibration problems are a function of tire balance. The exception to this is the new car with low profile tires that has been sitting for prolonged periods. If you have gotten this far in the web site you probably know what is causing your vibration. This phenomenon is often seen with imports as they sit in containers while crossing the ocean.

Other causes of vibrations are wheels that are out of round or warped. Aluminum wheels are very prone to this problem and the wider the diameter of the wheel, the greater the tendency for this to occur.

If you have a vibration problem we recommend the you seek out a Hunter model 9700-wheel balance system; they are diagnostics for most tire and wheel problems. We also recommend that when changing tires you select a system that does not touch the wheel while dismounting or mounting the tires.

There will rarely be tread separation or belt separation unless the tire has been run in an under inflated mode; still, this does occur and the problem is first manifested as a vibration.

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Vulcanization & Compounds:

As noted elsewhere in this web site, low profile tires with high, speed ratings tend to vulcanize rather rapidly. This occurs at about twice the rate of a 'regular' tire. There are several reasons for this; the first is the compounds that must be used in most of these tires, they have a finite number of heat cycles and harden with each heating and cooling. Also, they will vulcanize with age. That is, you don't have to drive the car much for the tire to vulcanize; just let the tire get old and it will get hard. Tire vulcanization and its' dangers have been addressed elsewhere in this web site.

The bottom line in performance tires is this; most people buy tires with a far higher tread life than necessary and the tires vulcanize well before they are worn out. This creates a dangerous situation as the vulcanized tire compromises traction while cornering, braking and accelerating. you would do well to consider the UTQG tread wear factor when you buy your next set of performance tires.

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Tire Care:

Short and sweet. Wash your tires with a good detergent and a brush and wash them every time you wash your car. Laundry detergent works very well. Do not put any silicone 'shine' product on your tires. If you use UV protecting agent, get one that is silicone free such as 303.

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