Aftermarket wheels have become a staple modification for enthusiasts. There is nothing you can do to a car that will have the visual impact of a new set of wheels.
We have assembled this list of lightweight wheels for the performance-minded driver. We have chosen to highlight 18- and 19-inch sizes, even though many of these wheels are available in smaller and larger diameters. We wanted to focus on wheels that could be used for double duty as street and track wheels. Since most European vehicles are now coming with 18- or 19-inch wheels as standard, or as a common option, they can be run in most racing series. Plus, most DOT R-compound tires are readily available in diameters up to 19 inches. We've driven on some 20-inch R compounds, but at the time of writing, they are still quite rare and not readily available to most consumers.
Why a lightweight?Style is usually the first consideration when selecting aftermarket wheels, because most wheels are purchased for their different-than-factory looks, helping to personalize the vehicle according to its owner's tastes. After that comes the functional requirements of selecting the diameter, width and offset that are right for the vehicle and appropriate for the desired tire size.
While all wheel styles evolve, there are some almost timeless classics, including some of the basic five-spoke, six-spoke and cross-spoke designs. And since the look of many classic designs have evolved from racing, their form follows function. This means their basic design helps an engineer balance style, strength and weight. On the other hand, there are also fashion wheels, which, like clothing, tend to change with the seasons. This means their designer (not engineer) has placed the emphasis on aesthetics over weight. And because most fashion wheels are expected to have relatively short lives, the ability to produce them economically, in small volumes, becomes an important factor. Unfortunately, this normally precludes using the most current high-tech manufacturing methods.
However, not so obvious is the role wheel weight plays in determining a vehicle's overall ride, performance and feel. This is why so many new vehicles have replaced the less expensive rolled, stamped and welded steel wheels with cast aluminum alloy wheels.
Ever since the development of the original mag wheels, which actually used a magnesium alloy to reduce wheel weight on the race cars of the 1950s, lightweight wheels, where permitted, have been used to enhance performance in almost all forms of racing. And while the generic mag name is still used today, most magnesium alloy wheels are too fragile for daily street use and are limited in their finish options, allowing only for painting or polishing. These days, the most common uses for magnesium wheels are on Champ Cars, Indy, Formula One and GT cars, where the teams' continuous monitoring and testing can confirm their strength and durability between events.
Mag wheels used on modern race cars are often forged or use some other high-tech manufacturing process and special magnesium alloys to reduce the weight, while retaining the ability to take high loads. Fortunately for the rest of us, manufacturers have also developed lightweight aluminum alloy wheels that provide appropriate street durability and numerous finish options while reducing weight.
A vehicle's total weight affects its ability to accelerate, brake and corner. Reducing total weight will enhance performance because less weight needs to be controlled and therefore less energy is required. Unsprung weight is the weight under the springs which moves up and down as the vehicle rides over uneven roads and leans in corners. Reducing unsprung weight allows springs and shock absorbers to be more effective in controlling the suspension's movement. Additionally, a vehicle's rotational weight includes all parts that spin, including everything in the driveline from the crankshaft to wheels and tires. Reducing the weight of any of these rotating components will enhance performance, because less energy will be required to increase or decrease speed.
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