Each E8 unit is equipped with the two Model 567 diesel engines, developing 2,250 horsepower. The E8 was EMD's most popular passenger diesel, and during the model's production run - August 1949 to December 1953 - the builder sold 454 "A," or cab, units and 35 "B," or cabless booster, units. "A" units featured an operation cab at one end for the crew, while "B" units contained the same mechanical equipment but were meant to be teamed with, and controlled from, a locomotive having an operating cab. Most diesel road locomotives are equipped with control cables that enable the to be operated in tandem from a common location in an arrangement called "MU", or multiple-unit control. In this way, the amount of power needed can be tailored to the weight of length of a train. E8s were the successor model to EMD's earlier 2,000 horsepower Model E7, which was produced from February 1945 to April 1949. The E8 used a car body that was almost identical to that of the E7. The main external difference was that the E8 sported stainless-steel air-intake grilles and four engine room portholes along each side of the unit in place of the E7's staggered rectangular air intakes and rectangular windows. Length: 71 Feet. Weight: 316,500 lbs. Tractive effort: 56,500 lbs. Horsepower: 2,250. Gear ratio: 55:22. Top Speed: 90 mph. Prime Movers: Two 12-cylinder Model 567 diesel engines. Fuel Tank capacity: 2,000 gallons. Crankcase oil: 660 gallons. Wheel Arrangement: A1A-A1A ( two six-wheel trucks, in which the leading and trailing axles are powered and the center axle is unpowered).