CorenDirebrew wrote:1: new GP38AC's appear
2.Widecabs such as a GP70MAC would appear with the original EMD safety cab because i hate the box cab in the ACe's and m-2's and not the 4 or 3 window cab.
3. Complies with the EPA Tier Emmision requirements
4. A refurbishment for the Older GP units with DC power and replace the DC power with a new AC power.
6.4 prive movers so if the others fail the back up will be on and the Geep will still move.
7.Passenger units called the GP70FH pulling trains
I'll adress your points one by one..
1.Canadian Pacific is buying a number of new GP22ECO units,which, although using the trucks,traction motors, and some other components from traded in GP9Rs will be brand new locomotives with new frames and 2,000 HP 8-710 engines, the modern equivalent of a GP38AC......
2.to build a 70 series locomotive with the newly required emissions system (requires a bigger cooling system,etc.), decent capacity fuel tanks and AC electrical equipment yields a unit that is much too heavy to ride on 4 axle trucks, so you need six axles. BNSF is getting a new order of SD70Aces that use CC trucks with the first axle in each truch unpowered, the equivalent of a GP70Ace with a couple of extra axles..
3. read my comments about the cooling system required by Tier compliance and the weight penalty they impose..
4. Older Geeps delivered with DC generators are commonly rebuilt with Alternators (the difference between a GP38 and GP38 AC,note the GP38AC DID NOT have AC traction motors like the EMD 70 series AC units ) but they retain DC traction motors. Retrofitting AC traction motors alondg with the other required AC traction components (inverters, ect.)onto a DC motored unit is extremely expensive. The only locomotives so converted in the US (otherthan test unit) were some ex -New Haven FL9s that cost almost as much as a new locotive would have..
6.that's a Genset locomotive which EMD parent company progress rail builds. It's not 4,000 HP though..
7. Again, a 4,000 HP AC unit built on a roadswitcher frame would be too heavy, EMD is designing new passenger units but they will use Monocoque carbodies like the GE Genesis units..
Basically the systems required for a modern,high horsepower road freight locomotive mean an engine that is too heavy for 4 axle trucks..