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Mopar enthusiasts likely recall that the GTX originated as Plymouth's performance take on the Belvedere before evolving into its own model. The approach paired the Satellite's plush interior with the standard 440 Super Commando V8 and upgraded suspension. Buyers received a 375-horsepower Plymouth, or 425 horsepower with the optional 426 Street Hemi, complete with bucket seats, abundant chrome, and woodgrain accents. Distinctive 1967 GTX touches included a console tachometer, simulated hood scoops, a darkened grille, and red tire stripes. At roughly $3,200 - about $500 above a Satellite Hardtop - it carried a premium price. Its elegant cabin, strong performance, and higher cost prompted fans to label it the gentleman's muscle car.

The GTX became a standalone model in 1968, yet its run proved brief before the name reverted to an option package after 1971. Plymouth promoted it as the Executive Branch of the Rapid Transit System. Roughly 12,000 units sold in the debut year, with only 125 featuring the 426 Hemi according to Hemmings, rendering those examples highly sought after. The 440 Six Barrel arrived for the GTX in 1970, a year after its Road Runner debut, so caution is wise when encountering a claimed 1969 GTX so equipped.

The GTX timeline

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Convertible GTX models ended after 1969. For 1970 the car became a two-door hardtop only, gaining a power-bulge hood and fresh styling such as revised quarter panels with simulated vents. The 1971 redesign introduced the fuselage body style. Muscle-car fortunes declined that decade, and the GTX suffered alongside them. Automatic and optional four-speed transmissions persisted, yet lower compression and emissions gear reduced output on some engines to 370 horsepower for the base four-barrel and 385 for the Six Pack, while the Hemi stayed at 425.

Later GTX examples are scarce, with roughly 7,700 built for 1970 and under 3,000 for 1971. By comparison, Porsche produced more than 4,000 units of the 991.2 GT3 RS. Although the GTX became an option package on the Road Runner for 1972 with the 440, and the Six Pack and Hemi were dropped, one factory 1972 GTX is known to have carried a Six Pack, part of a small group of V-code cars once said not to exist.