The Rarest Plymouth Muscle Car Ever Sold To The Public

The rarest Plymouth muscle car ever sold to the public is tied to the GTX nameplate and a specific engine choice. The article explains that from 1967 to 1974, “GTX” was central to Mopar’s muscle lineup, originally a Belvedere trim level before becoming its own model. It notes shared components with vehicles like the Dodge Charger, Dodge Coronet and Plymouth Satellite, including big-block options such as a 7.2-liter Magnum V8 and a 7.0-liter Hemi V8. After 1971, GTX returned to being a trim. The focus is on the 1972 Plymouth Road Runner GTX 440+6, detailing its 7.2-liter V8, 3-speed automatic, rear-wheel drive, 390 hp and 490 lb-ft. The key difference is the 440+6 engine, known as “Six Pack” or “6-BBL” depending on maker.