DETROIT—Amtrak plans to spend $7.3 billion to replace 83 passenger trains, some nearly a half-century old, though much of the funding must still be approved by Congress. Amtrak said Wednesday that under the contract with German manufacturer Siemens AG, some of the trains will be hybrids, able to operate on diesel fuel and electricity where wires are available. The new trains will replace Amfleet, Metroliner and state-owned equipment starting in 2024. The new engines and passenger cars will be built at a U.S. factory in Sacramento, California. The new trains will have more comfortable seating, better ventilation systems, individual power outlets and USB ports, onboard WiFi, and panoramic windows. Amtrak CEO William Flynn says they’ll pollute far less than the older trains when operating in diesel mode. The trains will go to lines in New York, New England, California, the Northwest, Virginia and elsewhere. The railroad has an option to …