Things changed between those nights when Mr. Valadez was getting stopped by cops suspicious of any long-haired kid in a car that rode inches off the ground and the days when they began pulling the balding, middle-age man over to admiringly gaze at his automobile.
Lowriding is high art these days, and Mr. Valadez, 61, who makes his living reupholstering cars, is one of its masters.
"I had no idea," he said, standing on a corner of East Los Angeles' Whittier Boulevard where some say lowriding was born. "I did say when I was building it, 'This car that I'm working on, people are going to hear about this car someday.' But it never dawned on me that it was going to become famous."
Known in lowriding circles the world over as the Gypsy Rose for the intricately detailed 150 red roses covering its body, Mr. Valadez's 1964 Chevrolet Impala, with its velvet seats and its chandeliers, is a centerpiece of the Petersen Automotive Museum's La Vida Lowriding (The Lowriding Life) exhibition.
SURROUNDING THE IMPALA are two dozen other tricked-out vehicles, including a pickup owned by musician Ry Cooder that holds an elaborate mural depicting the history of Chavez Ravine, the barrio shut down by authorities in the 1950s to make way for Dodger Stadium. Another is Dressed to Kill, a 1971 Buick Riviera with its eerie scenes of a graveyard at sundown. Its owner is Lowrider Magazine Editor Joe Ray.
"We call these the Faberge eggs of the car culture," said Dick Messer, the museum's executive director. "They are so incredibly well-executed when it comes to the paint jobs and inlays and gold leaf and silver leaf. There's an ice cream truck in the lobby it took the guy 12 years to build."
That would be the work of Mr. Cartoon, a mysterious figure who prefers to go by no other name. His day job is designing clothes and shoes, including several lines of the latter for Nike.
Since 1995, however, much of his spare time has been given over to a dilapidated 1963 truck he recovered from a South Los Angeles yard, overhauled, lowered and turned into an airbrushed work of art. Every inch is covered in tangerine, purple, yellow and other colors that depict clowns, balloons, ice cream sundaes and L.A. street scenes.
He takes the truck to schools to show how it helped a kid from the street turn his life around and become a "homeboy homeowner." His lifesaver is in the exhibit, which runs until June 8.
"Lowriding has always been the most lowbrow form of car culture," he said. "But out of it comes these beautiful works of art."
No one seems to know exactly where lowriding originated. Espanola, N.M., calls itself the "Lowrider Capital of the World." Others will argue that it began spontaneously in suburban neighborhoods around Los Angeles after World War II. Others cite Northern California.
"I don't think we'll ever pinpoint exactly where it started," says Denise Sandoval, a Chicano studies professor at California State University, Northridge, whose doctoral dissertation was on lowrider culture. "The reality is that it was popular everywhere in L.A. in the years after World War II. White guys were doing it, black guys, Chicano guys and they were all getting their parts from the same places."
It has spread to Europe and Asia, with people spending $100,000 or more to outfit cars with elaborate paint and upholster, lowered frames, hydraulics and earsplitting sound systems.
The pastime began to migrate out of the southwestern United States in the 1970s, Dr. Sandoval said, when Boulevard Nights, Corvette Summer, American Graffiti and other movies and TV shows began glamorizing lowriding.
It's very different from the day in 1970 when Mr. Valadez picked his car up for $150 from a GI headed off to Vietnam and used sandbags to lower the back. Now people of modest means will spend a good part of a lifetime customizing a car.
The Gypsy Rose is seen in the opening credits of the 1970s Freddie Prinze sitcom Chico and the Man; Mr. Valadez is at the wheel.
"It's not dissimilar to any type of pop culture," Dr. Sandoval said. "Once TV and movies get interested in it, it becomes a big business."
SOME OF THE BEST examples can still be found on the street.
On a recent Sunday, two dozen lowriders lined up their cars in the parking lot of a McDonald's in East Los Angeles. The sunshine dances off the cars' flashy paint jobs.
Among those gathered is Deputy Al Martinez, of the Los Angeles County Sheriff's Department, who is prepared for the look of surprise he gets when he reveals his day job.
For Deputy Martinez, 46, becoming a lowrider was pretty much destiny. He inherited his hot-pink 1966 Buick Riviera from his uncle. To him, the Buick is even more than a work of art.
"It's a family heirloom," he said.