The economy may be stalled, but the number of people working on their own cars and engines continues to grow. This is especially true of the attention Americans are lavishing on their wheels.  According to the most recent industry numbers, wheels and tire sales boomed last year, growing their slice of the $28 billion specialty parts market.

The industry might be new, but wheel culture is not. People have been tricking out rims in this country since the wagons went West. But rims didn’t become big business until the mid-’90s. That’s also when “rim inflation” exploded, taking us into the current world of 32-inch rims. It’s a world that earlier generations of car and wheel aficionados could not have imagined.

The story of how modern wheels blew up past 30 inches is a long and complicated one. Which came first: big wheels or big rims? “You’re going to get a different story from everyone you ask,” says David Zuckerberg, a pioneer in the development of donk culture.

Veteran observers say that the pendulum is beginning to swing. “I see standard sizes falling back and settling in between 18 and 22 inches,” says Quincy Jonathan of Victoria Tire & Wheels, the Los Angeles showroom that has been in the business since 1965. “It’s already starting to go down, and I’m seeing a lot of 24 inches right now.”

Whatever the size of the wheel, more people around the world are taking wheels seriously. The Asian market is growing, with China seen as the next big customer. We recently spoke to some custom car experts about how wheels became an art form, and what we can expect in the future.