In 1938 the Atlantic Coast Line received twelve 4-8-4s of class R-1 from Baldwin Locomotive Works. They were intended to replace smaller power and thereby eliminate double-heading or extra sections on the railroad's popular passenger service between Richmond, Virginia and Jacksonville, Florida. While eminently capable of handling the larger trains, the R-1s proved to have a problem with dynamic augment, or unbalanced pounding of the rails, when running at speed. Although Baldwin redesigned the drivers and running gear the problem was not fully corrected, and these handsome locomotives were reassigned to freight service as soon as the ACL could replace them with EMD E-3 and E-6 diesels.

With 80-inch drivers, the R-1s had cylinder dimensions of 27x30 inches and sustained 275 p.s.i. of boiler pressure. They had 4753 square feet of evaporative heating surface, 1425 square feet of superheating surface, and a grate are of nearly 98 square feet. Tipping the scales at 460,270 pounds, they mustered a tractive effort of 65,800 pounds. All driving axles had roller bearings, and the engine bed was a one-piece cast steel frame. No. 1809 of the R-1 class poses at Jacksonville on April 9, 1948 in an image from William D. Volkmer.