A Look at Wheel Weight, Density, and Stiffness

While most people ignore it, there’s still pretty common knowledge that tires are the most important part you can throw at a car. And it makes sense because the rubber on your wheels is all that keeps a car on the road. But if tires are so important, then it would mean that the wheels they are mounted on play almost as important of a role in vehicle performance, right?

Most tuners pick wheels for looks and by reputation. Racers swear that lighter wheels will enhance performance, but no one seems to know by just how much. So we took it upon ourselves to do a performance wheel test by rounding up five different makes of wheels and running them through a gamut of our home-brewed tests. Each wheel came in the identical 18x8.5-inch size with a +30et offset (a conservative size for our EVO 9 test car) and was shod in identical brand-new 255/35/18 BFGoodrich g-Force Sport spec tires.

Our test wasn’t about which brand of wheels is necessarily best. More important was the real-world performance difference, if any, between wheels manufactured by different methods, and how much bang you get for your buck. So we picked five different types of aluminum wheels—cast and forged, single or multi-piece—to put to the test. Each wheel is JWL certified and at least passes the basic JWL strength and durability tests for safety. We intentionally picked products that span the entire market of reputable aluminum wheels. This way, we’d be able to see the extent of difference as each wheel is put through our real-world tests.