I am wondering what the real difference between the SD70ACe is and the SD90MAC-H II is? The locomotive looks almost the exact same…? Also when did the 90 come out and is UP the only to order them? I know that KCS is leasing them now, so what was wrong with this engine? Any other input is also appreciated.
SD70ACe 4300hp ,
SD90MAC-H 6000hp.
The body style is similar but with good photos or if you were to see one of each model parked alongside each other there are external differences. The simplified cab design of the SD90MAC-H II was the inspiration for the cab used on the SD70ACe but it has been changed a bit. The other differences between the two locomotives The SD90MAC-H has a V16-265H engine while the SD70ACe has a V16-710G3C engine. The 265H engine is a 4-stroke cycle diesel like all GE engines while the 710G3 is a 2-stroke cycle diesel like all previous EMD diesels. The 265H has a larger displacement and uses twin turbos, while the 710G3 uses only one turbo. The SD70Ace is several feet shorter than the SD90MAC-H.
Two Railroads have or had SD90MAC-Hs Union Pacific and Canadian Pacific.
The Union Pacific has one batch of 22 SD90MAC-H with the older style body which they are keeping because the very favorable lease terms offset the low reliability of the locomotives. The second batch of 40 SD90MAC-H with the newer bodystyle are on a different lease with more expensive terms, these the UP is returning, and some have shown up on KCS. Canadian Pacific has 4 SD90MAC-H all with the newer bodystyle, for the moment they are keeping them. CP uses theirs between Winnipeg (their home shop) and Thunder Bay.
EMD owns 2 SD90MAC-H with the new bodystyle for test purposes, and also owns the only SD89MAC which shares the same bodystyle but uses a V12-265H engine.
glad some one knows i wonder about that myself i knew some but not all that info.
The external differences that I know of are the SD90s have 3 radiator fans while the 70s have two, the SD70s are a bit shorter, and have a bunch of exposed piping under the walks, unlike other EMD locos.
on an unrelated topic, why aren’t you ever on MSN anymore?
Wow thanks for the replies…
The Phase I SD90’s (the first 22 of UP’s) have three fans but the Phase II SD90’s have two radiator fans just like the ACe’s do.
They are way different, the second poster hit the nail on the head.
Speaking of SD90’s, I was over in Murphysboro piddling around the west side tracing the former GM&O route, on Dallas Road (which parrallels the UP for a good mile and a half) and caught a train, it had a SD90MAC leading a SD70M, and a SD40-2 (all UP) and the fourth being a leaser SD40-2 still in BN colors, on a mixed train. All I know is that the SD90 was in the 8200- series numbers.
The 8000 - 8308 series SD90MACs were built with a 4300hp V16-710G3C engine and were to be converted to the V16-265H engine when the bugs were worked out.
Since the bugs weren’t worked out they will keep the 710G3 engine. The UP calls these locomotives SD9043MACs, EMD calls them SD90MACs (no “H”).