To trace the genesis of the Challenger, you have to delve into the development of the 1970 Barracuda, which began in February 1967 in Chrysler's Advanced Styling Studios under the supervision of Cliff Voss. It was here that the main themes for the '70 Barracuda would be determined in conjunction with the Advanced Planning and Advanced Engineering groups. With the market shift from sporty to muscle, there was considerable pressure from top management to get the new platform right. The platform was to be called the E-body.

For Engineering, there was one absolute: The new E-body engine compartment had to be large enough to accept engines up to 440 ci along with air conditioning, power steering, power brakes, and other accessories. The ponycar had also become a muscle car, and in a market where there was no replacement for displacement-and where before the Barracuda had always come up short-Chrysler was determined that no one was going to have a more potent engine lineup.

To achieve this goal, the cowl from the larger B-body was assimilated into the design, permitting a large engine compartment. Advanced Styling was responsible for the area between the wheels, the "center section" of the car that housed the passengers. Voss' group set the guidelines for wheelbase, greenhouse, tumblehome, position of the side glass, and doorsills. Once the basic shell was approved by management, it was handed down to Plymouth Styling to define the outer skin.

Chrysler management also chose to give the platform to Dodge, initially as an upscale competitor to Mercury's Cougar. Dodge had been offered a version of the Barracuda in 1964, or the option of having its own 117-inch-wheelbase sporty car. Dodge chose the latter and introduced the '66 Charger, which was designed by a young stylist named Carl Cameron. Cameron, who had worked at Ford styling, was hired by studio chief Bill Brownlie in October 1962. While the decision to field the '66 Charger had eventually proven profitable, Dodge management realized it had missed out on the explosive ponycar market. Jumping in this late may have been viewed as poor timing, but by sharing some costs with Plymouth, Dodge could spread around the dollars spent and be profitable while selling fewer units.

The final designs of the '70 Barracuda and Challenger would be different from each other, although to the casual observer they looked similar. At the Dodge studio, Chief Designer Bill Brownlie commissioned his staff to work up the Dodge outer skin proposal. As the deadline approached, Brownlie contributed his own concept. Cameron, who supervised the Dart and Challenger platforms, remembers the skinning of the Challenger: "It was Brownlie's body side, which is the section through the door, that was selected." Brownlie chose to widen the body by flaring out the character line that echoes the profile of the upper beltline from the leading edge of the fender to the end of the quarter-panel. The Challenger also had a more pronounced Coke bottle effect in the quarter, kicking up the rear deck and then rolling down to meet the taillamp panel.

Chrysler's two ponycars didn't share much sheetmetal, nor did they have the same wheelbase. Originally, the Challenger's wheelbase was slated to be 111 inches, the same as the Dart. Cameron suggested reducing it by an inch. As Cameron remembers: "We were out in the 'stockade' where cars were viewed, and I suggested to Brownlie we shorten it so it would look different, it would be different, and it wouldn't seem that we were using the same chassis to build another body. Brownlie liked the idea and had it changed. It wasn't really that costly. We had talks with the engineers about the complexity, and remember, we used to build totally different floorpans just for dual exhausts. It wasn't that big of a deal then."

The Challenger's longer 110-inch wheelbase (Barracuda's architecture used 108 inches) picked up only a fraction of interior rear seat room over the Barracuda. The Challenger was longer at 191.3 inches to the Barracuda's 186.7 inches, and wider at 76.1 inches to the Barracuda's 74.7 inches.

The Barracuda also had a character line, but it extended horizontally along the flanks, just above the front and rear wheel openings. Like the Challenger, the quarter-panels kicked up to the high rear deck; however, there was a distinctive curl in the sheetmetal beginning at the rear of the upper door above the handle, defining the top of the quarter-panel and flattening out to the deck line. The wheel cutouts were also different. The Challenger's wheel openings were rounded at the top, and the sheetmetal actually kicked in before forming the wheel lips. The Barracuda's wheel openings were flattened at the top with no flaring.

Carl Cameron summed up the styling of the two cars: "To understand how significant the difference was between the Barracuda and the Challenger, consider the car as a loaf of bread, and remove a slice from the center. This slice is called a body section. The Barracuda's body section was clean and simple in the sense that it came right off the beltline, went out to a peak, and went right underneath with extreme tumble under. The Challenger's body section shows it kicked out a little more than the Barracuda, came down at an angle, flared out to the character line, and then back down and into the sill."

Although the budget wasn't available for Chrysler to develop urethane bumpers like GM (the 1968 Pontiac GTO's front end was all urethane), the Elastomeric bumper option was offered beginning in 1970. High-density urethane foam was molded over unchromed bumpers and then painted body color. It had all the appearance of the GTO's Endura bumper at much less cost. And, unlike the Endura, Elastomeric could be ordered for both front and rear bumpers.

The Challenger used more chrome and brightwork than the Barracuda for an upscale look. Dual headlamps were deeply recessed under the huge hood, and the grille was outlined with bright molding. "I did the grille very deep," said Cameron. "The Challenger was very flat-faced. There was not a very large physical air opening in that car. The lights were set back at an angle to funnel the air into that center opening." A large chrome bumper separated the grille from the lower valance panel with a large air inlet and round parking/signal lamps.

The standard Challenger hood swept up to the cowl and covered the wipers. The optional Power Bulge hood, designed by Rick Carrell and modeled by Ron Carson, featured twin scoops and concealed wipers. Both hoods had the name Dodge spelled out across the front.

Flush-fitting door handles and ventless side glass contributed to the smooth look of the Challenger's flanks. Around back, the deck latch panel was dominated by the large taillamps and a bright molding that capped the rear of the quarters and trailing edge of the decklid. The reverse lamp was in the center of the panel, a design that Cameron had trouble getting approved. "It had the name Dodge in it. That was the first time anyone had put a name in a back-up lamp. I had a heck of a time doing that because they didn't think it would meet state lighting standards."

The rear bumper echoed the front bar, and a radically rolled valance panel featured cutouts for the exhaust tips on optional V-8 engines with dual exhausts. The steeply raked windshield, rounded side glass, and wide body accentuated the Challenger's low profile.