If you grew up in the 80s and 90s, you may have noticed a shift in car designs, all the way from luxury cars to sports cars. It was as if the automotive industry decided that cars should no longer be shaped like a brick but rather a sleek, aerodynamic bullet.

The change may look sudden, but a more zoomed-out look at the timeline indicates that the line is quite blurred. However, the exact year the transition happened can be pinpointed for some automakers. For example, some cars of the early 90s, such as the Buick LeSabre, underwent a complete styling change within the same generation from 1991 to 1992.

Even though the shift remains underappreciated and ignored, it is the most distinct design change in the automobile industry across the past decades. Improving fuel economy, better technology, and new safety standards are all liable for the curvaceous modern cars we see on the streets.

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Classic Cars Were Boxy To Maximize Interior Space

1957 Cadillac Eldorado Brougham Parked
Mecum Auctions

Looking in the rear mirror of a modern American car, its line of ancestors gets boxier and boxier as you pan back to the 1930s. Cars were once just meant to be a transport medium to get from point A to point B, sometimes with a tad bit of extra comfort for extra money.

Our grandparents designed cars to be practical and functional. A boxy design was the best way to increase interior space. This is especially true for pre-90s luxury sedans that didn’t need to convince anybody that they were fast. Manufacturers prioritized maximizing trunk and cabin space by turning their cars into refrigerator-shaped rooms on wheels.

Classic American Curvy Interior
Rare Classic Cars & Automotive History via YouTube

Where space is not an issue, technology was. The lack of computer modeling meant that car manufacturers had to use wood and clay to model cars. As any carpenter will confirm, modeling curves using solid materials is difficult.

The olden days also lacked the means to produce smaller and more powerful engines. The average 8 and 16-cylinder powerplants sitting in the engine bays of old muscle cars had to be housed in a larger body. Producing larger cars was more expensive, and rough rectangular edges allowed automakers to save materials.

How A Fuel Crisis Produced Curvy Cars In The 90s

Classic American Curvy Interior
Boca Brothers Classic Cars via YouTube

There is one fuel crisis per generation, and those that were around in the 80s and 90s had it bad. A driving force behind the shift to curvy car designs was the need to improve fuel economy. The reason is physics. Without delving too deep into the science, curves make it easier for air to flow over the car, which means less resistance. Less resistance due to smooth curves translates to better MPG.

But it wasn’t just the automobile industry's concern about their customers spending big on fuel. Back in the late 70s, the government was cracking down on fuel economy. This meant new standards for car manufacturers were right on the horizon. They had to make cars that go further on less gas, and achieving better fuel efficiency wasn't cheap if they resorted to tinkering under the hood.

Dodge Viper GTS - Front
Mecum Auctions

That's where curves came to the rescue. Instead of producing better engines and spending fortunes on research, automakers used the obvious shortcut to improve fuel economy. By turning to aerodynamics, everyone in the supply chain gets to save some cash while speeding things up.

To meet regulations and cut down on fuel costs, every car on the market need to have exuberant curves. Engineers and designers were working together more than ever to make sure every inch of the car was aerodynamic. Gearheads have this to thank for the extra-curvy cars of the 90s everyone still loves, such as fourth-generation Mustangs.

Curvy Cars Looked Better Than Boxy Cars

1967 Porsche 911
Brian Snelso via Flickr

Fashion changes over time, and so does car design. A top hat and a suit were cool in the early 20th century, but everyone prefers jeans or shorts a hundred years later. Boxy cars were losing their cool as car enthusiasts steered towards curves, and car manufacturers picked up on this.

European cars were always curvy to conserve fuel, which saw sharper price hikes than in the US across history. Timeless, curvy European cars such as the Porsche 911 played their part in influencing the US, and soon European car designs were the new black. German standards for luxury were rising in popularity in the US, and American automakers added similar touches to their own vehicles.

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Classic American Cars With Impressive Curves

1953 Pontiac Catalina
Rogers Car Videos via YouTube

Curvy cars are not a brand-new concept. American-made luxury and muscle cars with smooth corners date all the way back to the Cord 810 in 1936. The history of the American automobile industry has several curvy cars spread across the decades.

In simpler terms, curvy cars were always there. Another classic example of a curvy car that roamed the pre-90 streets was the 1950s Corvette, which had visible European inspiration.

Boxy cars are out of fashion, but they haven’t vanished entirely. Some badges, like the Dodge Challenger, remain true to their origins, still sporting sharp corners in the 21st century. However, curvy cars are here to stay for the foreseeable future. And who knows, maybe someday we’ll look back at the cars of today and wonder why we ever thought they were sleek and modern.