BIRMINGHAM, Alabama – The growth of the NTT IndyCar Series will attract more engine manufacturers to join the series in the future, either through sheer interest or need, INDYCAR officials said Saturday.

“At some point it's not going to become a luxury (for engine manufacturers), it's going to become a necessity as we grow,” said Jay Frye, INDYCAR president. “We're not quite to that point yet, but we're getting close, so we're looking forward to who's next.”

INDYCAR announced last year that the NTT IndyCar Series’ two current manufacturers, Chevrolet and Honda, had agreed to an expansion to a larger 2.4-liter, 900-horsepower formula beginning in 2021. The series currently uses 2.2-liter engines capable of approximately 700 horsepower.

Frye indicated that the plan for the 2.4-liter engine is moving forward as planned, but the introduction date could change if it would aid new manufacturers entering the competition and Chevrolet and Honda were agreeable.

“It can move either way, I guess, at this point still,” Frye said. “Part of that will be the next OEM (original equipment manufacturer) partner, what their input would be or how they would want to go about it. Obviously, Chevrolet and Honda are very keen to have another one come in, so if another one came in and it was a delay or some sort of different situation, anything like that could be possible.”

During a wide-ranging news conference before Sunday’s Honda Indy Grand Prix of Alabama presented by AmFirst at Barber Motorsports Park, Frye and Mark Miles, president and CEO of Hulman & Company, owner of INDYCAR and Indianapolis Motor Speedway, discussed the growth of the NTT IndyCar Series and other aspects of INDYCAR’s present and future. Among the most pressing of those issues is the possible addition of more manufacturers.

“It's a huge commitment (for a potential manufacturer),” Frye said. “They have to build engines. The ones that we're currently talking to want to build their own engines, so that's a key indicator when you talk to somebody about their commitment. It's just really a timing thing at this point, so we're sorting through that.”

The expansion of NBC Sports’ coverage to include all NTT IndyCar Series practice sessions on its INDYCAR Pass on NBC Sports Gold subscription service has been received well by NBC, Miles said. In addition to practices, INDYCAR Pass will stream most qualifying sessions this season, have on-demand race replays shortly after each event, live Indy Lights presented by Cooper Tires races and ancillary INDYCAR programming.

“NBC seems genuinely pleased with it from a quantitative point of view, the number of (subscriptions),” he said. “From a qualitative point of view, all the feedback we've gotten has been very positive. Someday we'd of course like to have live races on it, but that's not our agreement at the moment, and that's an NBC consideration.”

Miles also praised the efforts of Barber Motorsports Park officials and ZOOM Motorsports, promoter of the Honda Indy Grand Prix of Alabama, which will have its 10th running on Sunday.

“They're folks we trust, and I think the relationship is mutual,” Miles said. “They're innovative and they're constantly working to be better.”

Race coverage begins at 4 p.m. ET on NBCSN and the Advance Auto Parts INDYCAR Radio Network.