F59PHI, in my opinion you make the right-of-way improvements, and then worry about upgrading equipment. Most of the track Amtrak operates on now is barely good for 79 (can we say CSX?) much less 125-150 MPH operation. There is a lot more than many think is necessary to upgrade track. 150 MPH operation not only will require tilting trainsets, but also 150lb rail (it could be more), 21-24 inches of ballast, as well as improved signals, grade crossing improvements or elimination, and likely a cab signal system. In order to get Acela off the ground Amtrak had to create ACSES (Advanced Civil Speed Enforcement System) which is a very difficult thing to implement over thousands of track miles. Currently 79 MPH track has 115lb rail, 9 inches of ballast, grade crossings, draw bridges, and trespassers. These are all things that would have to change before you can operate at higher speeds. So in my opinion Amtrak should continue with P-42's until 110 MPH operation is under the maximum speed permitted.