Road Runner Superbird (Superbird)

Homologation Arithmetic NASCAR's rulebook is the whole explanation for the Superbird. For 1969 a manufacturer had to build 500 road-going examples of a body shell before it could race, which is how Dodge came to sell the Charger Daytona. For 1970 the requirement was recast around dealer counts rather than a flat number, and published accounts do not agree on the multiplier: several state one car for every two Plymouth dealers in the United States, others one for every dealer. Both readings land in the same place - a target near 1,920 cars, roughly four times what Dodge had needed a year earlier. Chrysler internal notes of September 1969 record readiness for 1,920 winged Plymouths. Whatever the wording, the effect was that Plymouth had to build a genuine production run of a shape that made no commercial sense whatsoever.

The Debt Plymouth Owed Richard Petty Petty had left Plymouth for Ford after 1968, and the Superbird was in large part the cost of getting him back. It worked: he returned for 1970 and took 18 wins from 40 starts. Pete Hamilton, running for Petty Enterprises, won the Daytona 500 and both Talladega races. Roughly twenty Superbirds were built as competition cars, and unlike the racing Daytonas - which had aerodynamic panels hung on chassis that already existed - they were supplied to the race shops as bare bodies in white.

What Was Changed, and Why Chrysler had concluded that a new higher-output engine would be expensive and uncertain, and that drag reduction was the cheaper route to superspeedway speed. The Superbird's nose is about an inch longer and less angular than the Daytona's, with a wider cooling aperture that answered the overheating the Dodge had suffered. The wing height was set to put the aerofoil in clean air above the roofline rather than to clear the boot lid, which is a consequence rather than the purpose. The rear window was recessed and capped flush, and where Dodge blended and painted that joint at cost, Plymouth covered the welds with a vinyl roof - which is why almost every Superbird has one. The front fender scoops are the interesting case: Chrysler said for decades that they existed for tyre clearance, but documents from engineer Larry Rathgeb's files record exhausters above both front tyres worth a three per cent drag reduction, which explains why the holes needed covers at all.

One Season, Then the Rule That Ended It For 1971 NASCAR restricted special-bodied cars - Superbird, Charger Daytona, Ford Torino Talladega and Mercury Cyclone Spoiler II - to 305 cubic inches, more than 120 cubic inches below what conventional bodies were allowed, or else to a substantial weight penalty. The 305 was not a serious proposition: no parts commonality with the big blocks, around $4,000 an engine with three needed per car, and reliability doubts over race distance. Richard Brooks ran a 305-powered Daytona for Mario Rossi in the 1971 Daytona 500, and that was effectively the end. Plymouth abandoned the Superbird after one model year.

Unsold, De-winged, Then Rediscovered The road cars were a commercial embarrassment. Buyers found the shape absurd, dealers discounted heavily, and examples sat on lots into 1972. A number were converted back to conventional Road Runner front ends simply to sell them. That episode still shapes the market: it thinned the survivor population, put genuine nose cones and wings into circulation as loose parts, and created the category of car whose aerodynamics were removed and later refitted. The same shape that could not be given away in 1971 has since carried seven-figure results at auction.

The Superbird's specific liabilities are the parts that make it a Superbird. The nose cone is a bolted-on assembly of its own panels and brackets, vulnerable to impact damage, poor previous repair and misalignment against the standard fenders; correct-fitting reproduction cones and braces are made, which is convenient and also means original panels cannot be assumed. The pop-up headlight doors run on a vacuum mechanism that leaks and sticks with age. The reworked rear window is capped flush and the joint welded and then hidden under the vinyl roof, so corrosion there develops out of sight and is expensive to put right properly. Cooling deserves attention: the widened nose aperture was itself a fix for the overheating the Charger Daytona suffered, and a Superbird with a blocked or modified opening will run hot. Underneath, the car is a 1970 Chrysler B-body and behaves like one - floors, boot floor and quarter panels rust, torsion-bar front suspension bushings wear, and the front discs are period Kelsey-Hayes items of modest capacity for the weight. The 440 is durable; the Hemi is not a difficult engine but is expensive to service correctly. Owner accounts of long-stored cars returned to the road describe fuel tank replacement, a full brake overhaul and chasing electrical faults as the entry cost.

Identity first. The VIN carries the model code RM23 and an engine letter - U for the 440 four-barrel, V for the 440 Six Barrel, R for the Hemi - and the number should be corroborated by the fender tag, the broadcast sheet where one survives, and stampings on the engine, core support and trunk rail. RM Sotheby's and specialist dealers describe exactly that chain of verification in their catalogues, and its absence is the single largest discount on the car. The V.O.N. sequence establishes where in the run a car sits, and specialist listings routinely quote it. Then establish what the car physically is. Complete reproduction nose cones, wings, headlight doors and mechanisms, rear window plugs and fender extensions are all manufactured and sold, and full Road Runner to Superbird conversion kits exist, so a car wearing correct aerodynamics is not thereby a Superbird. Equally, a genuine car whose nose and wing were removed by a dealer in 1971 and refitted later is a genuine car with a broken paper trail; which of those two situations is in front of you is the question that matters. On condition, original quarters and floors are worth establishing, since the specialist trade advertises them as a distinguishing feature. Look under and around the vinyl roof at the flush rear window cap, where the welded joint is hidden and water collects. Check the nose cone mountings and its alignment to the fenders, and verify that the vacuum-operated headlight doors rise and fall together. On a car stored for years, expect fuel system contamination and brake work as a matter of course rather than as a fault.

As of August 2026 classic.com records an average Plymouth Superbird sale price of $311,634, with the market clearly stratified by engine: a benchmark of $530,780 for 426 Hemi cars, $264,805 for the 440 Six Pack and $223,271 for the 440 four-barrel. The lowest sale classic.com records is $90,000, on 11 December 2021, and a car offered at Mecum Kissimmee on 17 January 2026 failed to sell against a high bid of $375,000. Auction evidence tracks the same shape. RM Sotheby's sold a 440 four-barrel TorqueFlite car for $110,000 at Arizona in 2017, a 440 four-barrel automatic from Ray Evernham's collection for $220,000 at Auburn Fall in 2021, and a matching-numbers 440 Six Barrel four-speed for $242,000 at Hershey in 2024. The Hemi cars are a separate market and a volatile one: chassis RM23R0A172589 made $1.5 million hammer, $1.65 million with buyer's premium, at Barrett-Jackson Las Vegas in July 2022, and $380,000 hammer, $418,000 with premium, at Mecum Indianapolis on 17 May 2025. Both figures are real; neither is the Hemi Superbird market on its own. Documentation, original sheet metal and a verifiable engine code separate cars far more reliably than colour or mileage do.