Working on a story for Diesel World
about the Mack ED diesel, focusing primarily on the initial development. A have a fair bit of info on that but what I am having trouble learning is about the transition to END engines. I will touch on them as the successor to the ED but what I can't seem to find is info about the differences. I know they debuted three other displacements, 405, 457 and 605 cubic inches and all the references I see in various period publications through 1942 refer to the the original 519 ci as the "ED" and the others as "END." In 1943, that designation changes and the 519 changes nomenclature to "END519." Obviously I don't have every scrap of paper on this, but are there some Mack gurus here that can educate me on the differences between "ED" and "END."
Also, while I have your attention, when the ED debuted in 1938, in which model Mack trucks were they available? Maybe between '38 and '40. I have info on the wartime trucks.