The smooth straight-eight of the One Sixty and One Eighty Clippers, featuring a , nine-main-bearing crankshaft and hydraulic valve lifters, was the most powerful engine in the industry through 1947, exceeding Cadillac's V8 by . It could deliver in second gear overdrive and take the a car to over 100 mph on Packard's Proving Grounds banked oval track. In 1950, ten years after Packard's nonpareil nine-main-bearing 356 inline 8 debuted, Rolls-Royce copied the design for their nine-mained, F-head 346-ci B-80 inline 8, used only in a handful of Phantom IVs produced solely for heads of state, military vehicles, and Dennis fire trucks. Like Packard's 245-ci six used in junior Clippers, Packard's 1940–50 356 Super-8 engine was widely used as a marine engine.