600, 601, 602, 603, 604, 610 and 618 had the 244's intact. The others were modified with the Detroit HEP diesels. 605, 606, 612, 615, and 617 had modifications in them to quiet the noisy Detroit sounds. I'm not sure if those engines had CAT's placed in them in the 90's, but they were modified to quieter HEP's at that time. 607, 609, 611, 613, 614, and 616 retained the Detroit's until retired. You would notice the quieter engine by the modified grille in the back of the FA unit. 605, 606, and 612 were the first FA's to have the mod's in the Detroit's.