Plymouth Roadrunner Superbird 1970

Plymouth built the 1970 Superbird for exactly one model year, in exactly one body style, to accomplish exactly one thing: win at NASCAR and bring Richard Petty back from Ford. It did both. Then dealers could not give the leftovers away, and buyers had the wings removed to make them sellable. Today those same cars are six-figure collector pieces. Read on for how that reversal happened.

Very few cars have a mission statement you can write in a single sentence, and almost none have one that was accomplished and then rendered illegal within eighteen months. The 1970 Plymouth Road Runner Superbird did both. It exists because a rulebook allowed something, because a rival manufacturer had poached the sport’s biggest name, and because Chrysler’s engineers were willing to bolt a nose cone and a wing onto a production car and dare anyone to say it looked ridiculous. Everyone said it looked ridiculous. Dealers could not sell them. And then, decades later, the joke reversed itself completely, which is a story worth telling properly.

Built for One Season, One Body Style, One Purpose

The Superbird was a heavily modified Plymouth Road Runner, and it was the Plymouth answer to the Dodge Charger Daytona that had appeared the previous season. Available for one year only and only as a hardtop, the car was designed specifically to meet and beat the competition at NASCAR’s fastest tracks. The irony is that comparatively few examples ever raced, because on many circuits the standard Road Runner was actually the more practical choice. The aero cars earned their keep on the superspeedways, where the drag reduction mattered most, and everywhere else the added complexity was not worth the trade.

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The Wind Tunnel Did the Styling, Not the Design Studio

The shape came out of a wind tunnel rather than a styling studio, which is unusual for the era and completely obvious once you know it. The nose cone with retractable headlights lengthened the car by roughly nineteen inches and smoothed the airflow that a stock front end would have piled up against. Ground clearance was cut to about seven inches. The enlarged wheel well openings were there to clear larger tires, and the rear-facing fender scoops, contrary to persistent legend, were there to cover the cut-outs in the fenders rather than to feed air anywhere. Every one of those decisions was made in service of a number on a stopwatch, not a sketch.

The Wing Was Not Tall for the Reason You Think

The rear wing is where the mythology runs thickest. For years the standard explanation was that the enormous height put the wing up into clean, undisturbed air. The more prosaic truth is that the height was largely dictated by the need for the trunk lid to open fully underneath it. The wing makes little practical difference at ordinary road speeds and only begins meaningfully assisting handling above roughly 90 mph, where it provides genuine downforce over the rear axle. That does not diminish the engineering. It just means the most visually outrageous feature on the car was partly a packaging solution.

440 Four-Barrel, Six Pack, or the 135 That Got the Hemi

Power came from the 440 in two configurations, either a single four-barrel or the Six Barrel setup with three two-barrel carburetors, and above both of those sat the 426 Hemi, fitted to just 135 Superbirds. That Hemi count is the number collectors memorize, and it is the primary reason a Hemi Superbird occupies a completely different tier of the market than a 440 car. The Road Runner identity was carried through in decals rather than badges, including one on each side of the rear wing uprights and another on the driver’s door depicting the cartoon bird with helmet in hand, ready to go.

The Bribe That Brought Richard Petty Home

The human motivation behind the whole program was Richard Petty. Petty had left Plymouth’s racing effort for Ford, and the Superbird was in large part built to bring him back. It worked. Petty returned and did well in 1970, taking wins across multiple NASCAR events that season while running competitively in many more against a very deep field. The car he drove became one of the most recognizable race cars in American history, and its shape and paint scheme were later immortalized for a generation of children as a key character in the 2006 film Cars.

How NASCAR Killed It With a Single Rule

NASCAR then ended the experiment with a stroke of a pen. For the 1971 season the sanctioning body imposed a power-to-weight restriction on cars with aero-specific designs, effectively limiting the winged cars to around 305 cubic inches or forcing them to carry substantial additional weight to compete. Neither option was viable. The rule came about because these cars were running at speeds above 200 mph on ovals whose safety standards had been developed for much slower machinery, and the concern was entirely legitimate. The aero war lasted two seasons and was legislated out of existence.

The Cars That Sat on Lots Into 1972

On the retail side, the story was grim before it was glorious. The wing did not take the market by storm. Superbirds sat unsold on dealer lots as late as 1972, and a significant number had the wing and nose cone removed so they could be moved as ordinary Road Runners, a fact that now makes restored survivors and unmolested cars even scarcer. Every wing removed in 1972 is a car that either had to be painstakingly put back together decades later or was lost to the configuration entirely.

From Unsellable to Six Figures: The Long Vindication

The correction has been thorough. Well-documented Superbirds trade well into six figures, with values having climbed substantially over the past decade, and the 135 Hemi cars occupy a tier of their own where individual chassis are tracked by number. There is even an aftermarket conversion kit for owners who want to build a tribute from a standard Road Runner, which is a reasonable way to get the look without the anxiety of maintaining a genuine one. For a buyer today, the critical questions are all documentation questions: does the fender tag support the engine, does the nose cone hardware match factory practice, and can the car’s wing-removal history be accounted for. The car that dealers once begged customers to take off their hands is now the one nobody sells without thinking hard about it first, which is about as complete a reversal as the collector market has ever produced.

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