Beneath the plain sheetmetal of this mid-size Plymouth sat one of the rarest engines Chrysler ever sold to the public: the 425-horsepower Street Hemi, built for NHRA stock classes and barely civilized for the street. Only 677 Belvederes were built with it in 1966, a year before the GTX name even existed to advertise what was under the hood. Buyers got forged internals, dual four-barrel carburetion, and a torque curve that demanded a reinforced rear axle. It’s the missing chapter most muscle car fans skip straight past.
