The Electro-Motive Division's SD80MAC was essentially an identical sister to the successful SD70 line except for its increased horsepower. Much longer than any single locomotive EMD had before produced aside from its experimental DD series, the model did have some noticeable design changes from the SD70 series, aside from increased length. The model was the first EMD locomotive to feature the flared rear radiator design that had been a common trait of General Electric diesels dating back to the 1970 and the "Dash 7" line. While other railroads would take orders for the SD80MAC only Conrail actually purchased any units taking delivery of its fleet in the 1990s. Railfans have come to refer the locomotives as "Conrail Cadillacs" and after the railroad was split between CSX Transportation and Norfolk Southern the units were divided between the two companies. Today, NS operates all of its SD80MACs while CSX has since leased out many of its units to a Mexican railroad.
The EMD SD80MAC is virtually identical to the SD70 series except that it is rated at 5,000 hp instead of the SD70’s 4,300 hp, and as mentioned above its rear flared radiator sets forward of the rear of the locomotive. The unit is also very rare, albeit it is relatively new. Built in 1995 the SD80MAC was purchased by only one U.S. railroad, Conrail, which took delivery of 30 of them. Only 8 other SD80MACs are roaming around North America although all 38 are still in active service. Of the 30 SD80MACs Conrail purchased, 17 went to Norfolk Southern and 13 to CSX during the split of the railroad in 1999. Eight of CSX's SD80MACs are currently off of the property and in service on Mexican carrier Ferromex.
The SD80MAC's prime mover is variant of the engine used in the SD70 series, the model 710G3ES. The engine was a 20-cylinder design, the first Electro-Motive had employed in one of its locomotives since the SD45 series of the 1960s. The SD45 actually proved to be a quite successful model for EMD despite the fact that early examples of the locomotive had reliability issues with crankshafts snapping while in operation. Once the company was able to correct these problems by redesigning the locomotive's engine block the SD45 proved a reliable and powerful locomotive that can still be found in use all across the country today. For EMD's SD80MAC it never did suffer from reliability issues in terms of a problematic engine.
In many ways, the model was the continuation of the high horsepower race between GE and EMD that had been ongoing since the 1970s. This race peaked during the 1990s with the release of EMD's SD90MAC and GE's AC6000CW. While GE's model sold more units than EMD's both were plagued with reliability issues which essentially ended the race between the two companies. Additionally, railroads discovered that extremely powerful locomotives wasn't necessarily a good thing and to date, the generally accepted horsepower is somewhere between 4,000 to 4,500. The "MAC" designation of the SD80 means two different things. The "M" regards the locomotive as featuring the now standard wide, "safety" cab that has been a common feature on motive power since the FRA mandates its use in the early 1990s.
Also, the "AC" refers to the model featuring an alternator for increased tractive, in this case EMD's model TA22CA8. Up to that time the SD80MAC offered some of the highest tractive efforts of any locomotive the company had produced; 185,000 pounds starting and 137,000 pounds continuous. Interestingly, the Chicago & North Western was interested in purchasing new SD80MACs to further update its motive power fleet but was acquired by Union Pacific before being able to do so and its order was canceled. Additionally, Conrail was after more as well until the 1999 NS/CSX split also canceled its order (the railroads replaced this with SD70 variants instead).
For more reading on Electro-Motive locomotives the book EMD Locomotives from author Brian Solomon highlights the history of EMD from its earliest beginnings in the 1920s to its phenomenal successes in the mid-20th century. It concludes by discussing the company's decline into second spot behind General Electric in the late 20th century and eventual sale by General Motors in 2005. The book features 176 pages of EMD history and is filled with excellent photography and illustrations. Another good title the author has written is entitled, GE And EMD Locomotives: The Illustrated History, which provides a general history of both company's locomotive lines over the years. As with all of Mr. Solomon's books expect a well-researched and written publication with crisp photography.