One-of-None Plymouth Superbird With 4-Spd Overdrive Is a Half-Million-Bucks HEMI Surprise

That’s the story of the 1,920 Plymouth Road Runner Superbirds that met the governing body’s conditions, allowing Richard Petty to drive a winged warrior during that season. Several bureaucratic inconsistencies make it hard to decipher how many were assembled – 1,935 is the most circulated variant. Of three details, we can rest assured they’re beyond a shadow of a doubt: they’re highly collectible, prohibitively expensive, and not easy to come across.

Out of the less-than-2,000 units assembled, the least numerous is the HEMI-powered version, with 135 winged Mopars receiving the 426-cubic-inch honors. The others carried the 440 Super Commando, either with the traditional single four-barrel carburetor or the Six-Barrel pack of triple two-throat carbs.

Naturally, the most prodigious are the 7.0-liter hemispherical-heads ‘Birds, again divided into two sections (based on transmission): three-speed autos or four-speed manuals. The latter was installed in 77 Superbirds, and here is one of those rare examples.

Located in Edmonds, Washington, the super-desirable Mopar has a skeleton under its big hood: the motor. However, a proper second-generation 426 HEMI with dual four-barrel carbs is not the original unit. There’s no info about the fate of the factory-installed powerhouse, but the replacement is date correct.

Another eyebrow-raising aspect is that the engine sports several modifications over the initial setup. The 426 HEMI was over-bored 0.020 inches over and fitted with Direct Connection pistons, stylite valves, and valve seats. The rebuilt HEMI has around 10,000 miles on it (16,000 kilometers). The odometer reads 84,148 miles (135,400 km).

The transmission is a four-speed, but again, it’s not the matching numbers gearbox. An 833 with overdrive makes the car more fun to drive, according to its long-time owner. The good news is that the 18-spline tranny is still around and ready to be installed back under the rejuvenated body of this one-year-wonder speed demon.

To keep the HEMI cool, a five-core radiator was fitted, most probably during the 2010 restoration, when the car received new sheet metal from the doors back, a trunk floor, new wheel housings, a rear panel, and rear quarter panels. Needless to say, it was also repainted in Blue Metallic, and new carpets, sound deadener, seat covers (front and rear), headliner, vinyl top, and a clear front windshield were installed.

The other signature feature of any Superbird (or the other winged warrior Mopar's, the Dodge Charger Daytona of 1969, for that matter) is the front cone, and this odd-Bird has also gotten a nose job (all metal). The correct tire choice was discarded in favor of radials. Several cosmetic touches were thrown in – the Road Runner decals on the wing's vertical struts, left headlight cover, steering column, and door panels.

The car is a two-owner example (the current one bought it in 1982) that belonged to a Chrysler boss from Texas. In 1971, the Superbird was released through the Race Drivers Program – maybe this would explain what happened to the original HEMI motor. The seller should be contacted directly by those curious about its complete history. And for those really curious, the price for that piece of history is $525,000 (the car and its full info).