SD70AC 4714

Did the nose letters on this CSX unit peel off, or were they taken off? http://www.railpictures.net/viewphoto.php?id=99134.
Reminds me of this picture.
http://www.trainweb.org/csxphotos/photo ... /2814m.jpg
keep asking keep learning

Well for starters that is an SD70AC (yes there is a difference) and the letters did probably fell off.

They were there back in November when I had that as a leader.

i thought that was a SD70MAC, the ACE's noses are shaped very different from SD70M's and MAC

SEPTALRV9072 wrote:Well for starters that is an SD70AC (yes there is a difference) and the letters did probably fell off.

Conrail used to call them "MAC's". The "M" was for widecab, and "AC" for the traction. Why, I don't know because they had the same whisper-cabs that the SD60I's have. Maybe it sounded better than calling them "SD70IAC". The old ones are similar to the new ones. CSX prefers to call them SD70AC. In fact, the ones inherited from Conrail are catagorized as same. The letters possibly were not applied in proper conditions. They're probably vinyl, and personally having done some part time work laying vinyl, if you don't do it right, they come off easy.

CSXT 4714 is a model SD70MAC-TI in the 4701 number series (as opposed to the model SD70MAC units in the 700 series). CSXT has assigned class "SD70AC" to both models. The model SD70ACe units are numbered in the 4831 series.

What is different with the SD70MAC-TI as opposed to the "standard" 70MAC?

charlie6017 wrote:What is different with the SD70MAC-TI as opposed to the "standard" 70MAC?

The SD70MAC-TI is the SD70MAC that complies with the Tier I emissions regulations that were in effect during the time period that the units were built. These are the SD70MAC's with the flared radiators, which have a redesigned cooling system.

Bryan Jones

One more difference:

The 4700-series units are rated at 4300 hp, while the 700-series are rated at 4000 hp.

CSX decided to have all of the 700-series uprated to 4300 hp.

ACLfan

Thanx for the info!

charlie6017 wrote:Thanx for the info!

actually CSX DO KNOW that they are sd70mac. But their problem is that their software system as I remember few years ago only have 6 slots in the program. So they drop one letter and "M" became victim...

I dont know if since that time, that has been changed or software had been upgrade to increase to 7 slots..

ken

The 4700's have a nice feature where you can set the speed control with the dynamic brake for speeds of 10mph or less. It helps when you have 10 mph slow orders on long decending grades. Up until the 4700's came out the AC motors I have come across only allowed you to use speed control feature using the throttle.