The 2,000 hp (1,500 kW) was achieved with two EMC model 567 V12 engines developing 1,000 hp (750 kW), each engine driving its own electrical generator to power the traction motors.
The front noses of the EA, E1A, E3A, E4A, E5A, and E6A cab units had a pronounced slant when viewed from the side. Therefore, these six models have been nicknamed "slant nose" units. Later E-unit models received the same blunted "bulldog nose" as the F-units.
Ironically, the E4 was produced before the E3. Both models were identical, save for the E4 having a pneumatically-operated nose door passageway in order to facilitate crew movement between units in a locomotive consist.
Marre, Louis A. (1995). Diesel Locomotives: The First 50 Years: A Guide to Diesels Built Before 1972. Railroad Reference Series. Waukesha, Wisconsin: Kalmbach Publishing. ISBN978-0-89024-258-2.
Solomon, Brian (2010). Vintage Diesel Power. Minneapolis, Minnesota: MBI Publishing. ISBN978-0-7603-3795-0.
Solomon, Brian (2011). Electro-Motive E-Units and F-Units: The Illustrated History of North America's Favorite Locomotives. Minneapolis, Minnesota: Voyageur Press. ISBN978-0-7603-4007-3.
Solomon, Brian (2012). North American Locomotives: A Railroad-by-Railroad Photohistory. Minneapolis, Minnesota: Voyageur Press. ISBN978-0-7603-4370-8.
Wilson, Jeff (2002). E Units: Electro-Motive's Classic Streamliners. Classic Trains / Golden Years of Railroading series. Waukesha, WI, USA: Kalmbach Publishing. ISBN0890246068.