A custom car is a phrase that became prominent in American pop culture in the 1950s, and has enjoyed special interest popularity since that time. It relates to a passenger vehicle that has been modified in either of the following two ways. First, a custom car may be altered to improve its performance, oftentimes by altering or replacing the engine and transmission. Second, a custom car may be a personal "styling" statement by the re-styler/re-builder, making the car look "unique" and unlike any car that might have been factory finished.
A development of hot rodding, the change in name corresponded to the change in the design of the cars being modified. The first hot rods were pre-WWII cars, with running boards and simple fenders over the wheels. These were modified by removing the running boards and either removing the fenders entirely or replacing them with very light "cycle fenders". The object was to put the most powerful engine in the lightest possible frame and body combination. The suspension was usually altered to make the car lower; the front was often made much lower than the rear. Much later some hot rods and custom cars swapped the old solid rear axle for an independent rear axle, often from Jaguar. Only rarely was the grille of one make of car replaced by another; one exception was the 1937 Buick grille, often used on a Ford. The original hot rods were plainly painted like the Model A Fords from which they had been built up, and only slowly begun to take on colors, and eventually fancy orange-yellow flamed hoods or "candy-like" deep acrylic finishes in the various colors.
With the change in automobile design to encase the wheels in fenders and to extend the hood to the full width of the car, the former practices were no longer possible. In addition, there was tremendous automotive advertising and subsequent public interest in the new models in the 1950s. Hence custom cars came into existence, swapping headlight rings, grilles, bumpers, chrome side strips, and tail lights, as well as "frenching" and "tunnelling" head- and taillights. The bodies of the cars were changed by cutting through the sheet metal, removing bits to make the car lower, welding it back together, and adding a lot of lead to make the resulting form smooth (hence the term "lead sled"; lead has been replace by Bondo). By this means, "chopping" made the roof lower; "sectioning" made the body thinner from top to bottom. "Channeling" was cutting notches in the floorpan where the body touches the frame to lower the whole body. Fins were often added from other cars, or made up from sheet steel. In the custom car culture, someone who merely changed the appearance without improving the performance substantially was looked down on.
Paint was an important concern. Once bodywork was done, the cars were painted unusual colors. Transparent but wildly-colored candy-apple paint, applied atop a metallic undercoat, and metalflake paint, with aluminum glitter within candy-apple paint, appeared in the 1960s. These took many coats to produce a brilliant effect -- which in hot climates had a tendency to flake off. Customizers also continued the habit of adding decorative paint after the main coat was finished, of flames extending rearward from the front wheels, and of scallops, and hand-painted pinstripes of a different color than the rest of the car. The latter, most often a single coat, would be expected to be of a simpler paint. Flame jobs later spread to the hood, encompassing the entire front end, and have progressed from traditional reds and yellows to blues and greens and body-color "ghost" flames.
Painting has become such a part of the custom car scene that now in many custom car competitions, awards for custom paint are as highly sought after as awards for the cars themselves.
Once customizing post-war cars caught on, some of the practices were extended to pre-war cars, which would have been called fendered rods, with more body work done on them. An alternate rule for disambiguation developed: hot rods had the engine behind the front suspension, while customs had the engine over the front suspension. The clearest example of this is Fords prior to 1949 had Henry Ford's old transverse front suspension, while '49s had a more modern suspension with the engine moved forward. However, an American Museum has what could be the first true custom, built in 1932, amongst its exhibits.
With the coming of the muscle car, and further to the high-performance luxury car, customization declined. One place where it persisted was the US Southwest, where lowriders were built similar in concept to the earlier customs, but of post-1950s cars.
Recently, as the supply of usable antique steel bodies has given out, a new trend to fabricate new steel and fiberglass bodies, closely based on the styling of the pre-war cars. Bodies of this type can cost over $100,000 before the running gear is added. California's "junker" (or "crusher") law, which pays a nominal sum to take "gross polluters" off the road, has been criticized by enthusiasts (and by SEMA) for accelerating this trend.
Starting in the 1950s, it became popular among customizers to display their vehicles at drive-in restaurants. Among the largest and longest lasting was Johnie's Broiler in Downey, California. The practice continues today, especially in Southern California.
Several customizers have become famous within the custom community, including Boyd Coddington and George Barris who spread their influence beyond automotive enthusiasts, thanks to the closeness of Hollywood; Barris designed TV's Batmobile, while Chapouris built the flamed '34 five-window coupé in the eponymous telefilm "The California Kid". Another Barris creation, Ala Kart (a '29 Ford Model A roadster pickup), made numerous appearances in film (usually in the background of diner scenes and such), after taking two AMBR wins in a row.
The most coveted award for customizers is the AMBR (America's Most Beautiful Roadster) trophy, presented annually at the Oakland Roadster Show since 1948. This competition has produced famous, and radical, customs, notably Silhouette and Ed Roth's Mysterion, some of which were turned into Hot Wheels cars, among them The Red Baron.
Others became notable for their appearances in film (such as Ala Kart, The California Kid five-window, or the yellow deuce from "American Graffiti") or television (such as The Monkeemobile, the "Munsters" hearse, or, more recently, Boyd's full-custom "Tool Time" '34 or '33 three-window, Eliminator, built for the ZZ Top video). Specialist vehicles, such as the T/A, KITT, from "Knight Rider", are not usually considered customs, but movie or TV cars, because they retain a mostly stock exterior.