Plymouth's 1967 GTX was based on the Plymouth Belvedere and was called a "luxury" muscle car. The 1st Gen GTX was a classy car but is remembered and sought after as a muscle car. The top engine offered for the GTX was the 426ci Hemi making 425hp. Leaving little doubt that this was a performance-oriented car. The Hemi cars are far rarer after just 733 of the 12,010 were given the massive powerplant. Only 312 Hemi cars were equipped with a four-speed manual. The price may have been a deterrent at the time with the premium being $546 for the Hemi.