Amtrak is seeking $1.3 billion in federal funds for major improvements to the heavily traveled Northeast rail corridor, including $450 million to make Philadelphia-to-New-York trains the fastest in the country, Amtrak said Monday.

A recent decision by the new governor of Florida to reject federal money for high-speed rail development there made it possible for Amtrak to seek the high-speed-rail funding.

The $450 million sought for the Philadelphia-New York stretch would pay for signal and track upgrades, improved power substations and overhead wire systems to increase capacity and boost speeds between Morrisville and New Brunswick.

The changes would allow Amtrak to increase service between New York and Philadelphia and increase the speed of trains on part of the route to 160 miles per hour. The current top speed there is now 135 miles an hour.

The work is slated to be finished by September 2017, if Federal Railroad Administration approves the funding, Amtrak spokesman Steve Kulm said Monday.

Other projects planned by Amtrak as part of the $1.3 billion funding include elements of Amtrak's proposed "Gateway Project" to increase capacity and reliability into New York City:

A new bridge to replace the century-old Portal Bridge across the Hackensack River. The old movable bridge is a choke point for train traffic in and out of New York, and its replacement could improve service for both Amtrak and New Jersey Transit trains. Amtrak proposes to spend $720 million, including up to $150 million from New Jersey, with work to be completed by September 2017.

Preliminary engineering and environmental work for two new tunnels under the Hudson River into Manhattan. Amtrak proposes spending $188 million, with work to be done by June 2015.

Engineering and environmental analysis to expand Pennsylvania Station in New York, on a site between 30th and 31st Streets and Seventh and Eighth Avenues. Amtrak has asked for $50 million to complete that preliminary work by September 2015.

The Gateway Project is a key part of Amtrak's long-term goal to build a new high-speed Northeast Corridor rail route that would allow trains to make the 426-mile trip between Boston and Washington in 3 hours and 23 minutes (compared to the current 8 hours on Amtrak's Northeast Regional trains or 6 hours and 37 minutes on Acela Express).

The proposed new high-speed service between Washington and Boston, with trains that could travel at 220 miles per hour, would require its own dedicated tracks and a new route north of New York away from the congested seacoast.

That proposed high-speed system would cost about $117 billion and take up to 30 years to complete, Amtrak president Joseph Boardman has said.

Amtrak said Monday that it also was seeking $15 million to begin engineering design work and environmental analysis to replace the Pelham Bay Bridge that crosses the Hutchinson River in the Bronx, on the Hell Gate Line linking New York to New England.

Contact staff writer Paul Nussbaum at 215-854-4587 or pnussbaum@phillynews.com