As the classic muscle car era was coming to a close, Chrysler engineers wanted to create a HEMI that was smaller, lighter and more affordable. The result was the A279 engine, also known as the Ball Stud Hemi. It got this name from the engine's new ball-stud rocker arms (like a big block Chevy) designed to trim weight and cost while also allowing the engine to fit in a wider variety of vehicles. Chrysler engineers originally planned for a 396 cu-in and 440 cu-in Ball Stud Hemi, but a few extra cubic inches made their way into the final prototypes for both performance and marketing reasons. The result was a 400 and 444-cu-in V8, with the latter said to be comparable in performance capability to the existing 440 Magnum V8. The Rarest Hemi Engine Ever Made And Its Tragic Tale (hotcars.com)
