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Most new luxury and sport cars come equipped with alloy wheels. Most consumers however, are unaware of the benefits they offer, aside from aesthetic appeal.
Steel wheels have been common for more than half a century. They are far more practical than the high-maintenance spoke wheels they replaced. Added hubcaps gave way to full wheel-covers, in an attempt to refine their appearance.
Practicality however, soon took a backseat to the pursuit of better performance. Racers identified a need for lighter weight and stiffer wheels, and mag wheels were born. These expensive race wheels were the forerunners for our modern day alloys.
No longer made of magnesium, most are made of an alloy of aluminum and other metals. The resulting hybrid is lighter than steel, stiffer than steel, and dissipates heat better than steel.
Lighter wheels require less effort to get them rolling, improving straight-line performance. Alloy wheels flex much less, promoting better handling through the curves. Another advantage is as obvious as the nose on your face…
Aside from the design of the spokes, most people quickly notice the brake mechanism peeking through. That’s a good thing! Visible brakes are cooler brakes. Cool brakes perform better and last longer.
When offered as a factory upgrade for a particular vehicle, the alloy wheels are usually larger in diameter than the steel counterparts. The manufacturer pairs the larger wheel with a tire that maintains the standard outside diameter. In other words, the new tire is just as tall, but has a smaller sidewall to accommodate the larger wheel.
Since sidewall flex is reduced by these low profile tires, the resulting tire/wheel combination increases performance considerably. Another reason to maintain this outside diameter is to ensure speedometer/odometer calibration. Larger tires rotate less over the same distance traveled on smaller tires—registering a slower speed as well as shorter distance traveled.
Unfortunately, smaller tire sidewalls reduce cushioning when hitting a curb or driving over a pot-hole. Ride quality suffers, and your precious alloys could possibly crack or break under such conditions. Manufacturers don’t usually fit their vehicles with dangerous combinations, but care should be taken when choosing wheels and tires from after-market sources.
Another consideration should be backspace, or off-set. This can be described as the geometry of the wheel on a horizontal plane. In other words, how wide the wheels sit in the wheel wells. Straying from stock dimensions can add stress to suspension components and lead to eventual damage. This damage is not covered under manufacturers’ warranties. Unfortunately, most consumers want the widest wheel that will fit within the wells, ignoring the potential risk to their suspensions.
Never the less, upgrading to alloy wheels can be the easiest way to increase your vehicle’s performance and appearance. If your vehicle doesn’t have them, consult an experienced professional about your options.