Amtrak is helping out by towing them to 30th Street Station during off-peak hours late Friday evening.
Officials say SEPTA crews will need a week or two for inspections and training before they can use them.
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The rail cars will provide some relief after months of delays, cancellations, and overcrowding, mainly due to mechanical issues for one of the largest and oldest fleets in the country.
The $220 million of state money allocated by Pennsylvania Gov. Josh Shapiro right before Thanksgiving is helping to cover capital expenses.
That money is also going toward repairs to the fleet of more than 220 Regional Rail cars that the federal government says must be fixed after several large fires.
SEPTA was on track to have Regional Rail services fully restored by Christmas, but they ran out of the thermal wire needed to help prevent fires.
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SEPTA officials say they've ordered all the available thermal wire they could find in North America, and they now have to wait for a shipment next week.
"It's going to continue to be an around-the-clock effort to push more of this fleet out into service," said SEPTA spokesman Andrew Busch. "We'll just have to stop on the thermal wire for a little bit, wait for that supply to come in, and then we'll get back to it."
On top of that, SEPTA is also in the middle of major union negotiations, which are set to resume Friday afternoon.
TWU Local 234 represents the largest portion of the workforce, and includes 4,500 members in Philadelphia who run bus, subway, and trolley services, officials said.
Regional Rail workers are not part of these negotiations.
SEPTA has 17 different unions, but officials say a deal with Local 234 will set the tone for other negotiations that are also happening.