CONCORD, N.C. – There are still many issues to resolve (namely, scheduling, track conditions, tire compounds are among myriad logistical challenges) about the viability of an IndyCar-NASCAR doubleheader race weekend.

But as Josef Newgarden’s Dallara-Chevrolet whizzed around the 17-turn, road course at Charlotte Motor Speedway under the watchful eyes of stars and executives from both NASCAR and IndyCar, there was no doubt about the infectious buzz for a marriage between the two biggest series in American motorsports.

That was evident from the smiles on the faces of Joey Logano and Ryan Blaney, who sent their Team Penske compatriot off from the pits and then greeted him in victory lane.

“We need to have a doubleheader, man!” Newgarden exclaimed to Blaney and Logano shortly before making the first laps in an Indy car at the track in more than 20 years. “And we need to do the ride swap.”

After watching his teammate turn six blazing laps, Logano was ready to trade in the keys from his No. 22 Ford for a test drive.

“You’re grabbing another gear, we’re hitting the brakes your first lap on the frontstretch,” Logano told Newgarden with a bemused laugh.

“The NASCAR guys, I love they’re interested in us, and we’re interested in them,” Newgarden, who clinched his second NTT championship five days earlier, told NBCSN’s Rutledge Wood. “You can tell we’re just racers. They love our race cars. I love theirs. The only thing that would have made me more excited would have been if I would have been able to get in one of their cars today.

IndyCar president Jay Frye, who was on hand as an observer along with Indianapolis Motor Speedway president Doug Boles, was highly encouraged by the enthusiasm.

“It was spectacular,” Frye said. “All the Cup guys were out watching the big board, obviously there’s interest from (the news media), from us. What’s next for all of us is something we’re working on, and it’s great we certainly felt welcome and wanted here. This is a great facility. So who knows? Lots of things are possible.”

Newgarden’s biggest concern was about how the tire compounds would mix (IndyCar uses Firestone; NASCAR is on Goodyear), but that turned out fine, as did the track’s banking and transitions that caused a “heavy” wheel because Indy cars have no power steering

“It was getting better each run,” Newgarden said. “It felt pretty good.”

.@JosefNewgarden was flying at @CLTMotorSpdwy! He ran some laps in a @Team_Penske Dallara @IndyCar at the ROVAL, a hybrid of the oval and infield road course. Full test is up on our Instagram. pic.twitter.com/rpLAMELXQC — IndyCar on NBC (@IndyCaronNBC) September 28, 2019

He said his fast laps were in the 67-second range, or about 14 seconds faster than William Byron’s pole speed (80.9 seconds) 30 minutes earlier – which was exactly the spread that had been predicted by Team Penske simulation software (according to Blaney).

Mindful of Team Penske president Tim Cindric’s playful yet stern warnings (“I told Josef we’re not going to get a trophy for what happens today. That million dollars for winning the championship won’t go far in replacing this thing. Have fun, but it’s on you.”), Newgarden said he took it easy in the Dallara-Chevrolet that Simon Pagenaud finished fourth with last Sunday at Laguna Seca Raceway, leaving “another second or two” on the track.

With a setup optimized for qualifying, it’s conceivable that he could have lapped in the 1-minute range and left his Cup teammates fully in the dust – though showing up NASCAR was far from the goal for Newgarden, who bent over backward being magnanimous toward his stock-car counterparts.

The two-time IndyCar champion talked multiple times about his dream of running a Cup car (practically begging Cindric for the opportunity during a news conference) and effusively praised the reception he received from NASCAR fans, noting that it likely would have been different during the Cold War the series engaged in through much of the 1990s and 2000s.

“I think everyone was really supportive of what we’re doing,” Newgarden said. “There just seems to be a lot more movement to racing fans being racing fans again. I love that because I’m a huge NASCAR fan myself.

“It doesn’t matter that I grew up racing open-wheel cars. I still appreciate top-level racing, and these guys are the best at what they do. They feel the same way about us. This whole discussion that’s emerging about trying to promote racing as a whole is a really great thing. I love it. I’m so interested in what they do all year, and I think it’s the same from their side, so the more we can do together in the future the better.”

How soon that will happen was the big question lingering over Friday’s exhibition, which Clint Bowyer referred to on NASCAR America as “the first test session for IndyCar on our Roval. Why wouldn’t we bring those guys to race with our sport? I think it’s a great idea.”

The chatter around an IndyCar-NASCAR doubleheader began to reach a fever pitch in May when NASCAR on NBC analyst Dale Earnhardt Jr., Newgarden and many others expressed interest (in an NBCSports.com story) about bringing the series together.

Executives from NBC Sports Group, which broadcasts the Indianapolis 500 and full IndyCar schedule and the final 20 races of NASCAR’s Cup season, also has expressed interest in the concept. NBC Sports recently cross-promoted the series in a humorous commercial with Roger Penske, Blaney and Pageanud.

“That was a lot of fun and a lot of great response to it, and that’s things we couldn’t have done in the past,” NBC Sports executive producer Sam Flood said last Friday in a news conference at Laguna Seca Raceway. “I think that’s part of us leaning in at NBC in trying to grow all of motorsports, and it’s important that every form of racing gets attention, and that’s what we’re pushing.”

IndyCar CEO Mark Miles has vacillated publicly on the idea. Asked by NBC Sports last week if IndyCar was moving toward a doubleheader weekend, Miles said it was unlikely before 2022.

“It was said that there was momentum in May. In my view there was more discussion in May, more talk about it, more smoke than fire. So I think the folks at NASCAR know that we think it’s a good idea. I think as far as I can tell, they think it’s a good idea.

“So we’ll see if it can be pulled together. But it’s something that we think, if it gets more people watching motorsports, it’s well worth working on.”

However, at least one person with direct knowledge of the talks (but not authorized to discuss them publicly) told NBCSports.com that a 2021 doubleheader hadn’t been ruled out.

Friday’s exhibition run was described by Newgarden as a “gift” from sponsor ShellPennzoil (“the coolest thing all week” during his championship celebration), which also has a strong business relationship with Charlotte Motor Speedway.

Track general manager Greg Walter described his contact with IndyCar officials about a race as preliminary, “first date”-level conversations. Walter was encouraged by Newgarden’s results.

There probably would need to be changes made with Indy cars (such as removing the “turtle” curbs that cause massive damage to Cup cars as a penalty for veering off course), but Walter said Charlotte is exploring IndyCar and other series (such as IMSA, support sports cars circuits and Formula E) for its Roval layout.

“We’re open to any form of racing if it makes sense,” Walter told NBCSports.com. “So if it physically and financially makes sense, and from a fan following if it makes sense, we’re open to it. NASCAR has been our focus and continues to be our focus, but we always ask is there something else out there that fits as well.”

Frye, who has boundless contacts in NASCAR from many years as a team and sponsor executive, said Newgarden’s car “looked very natural out there, looked good. The lap times were within reason of what everyone thought it would be. So, who knows?

“There really aren’t any hurdles (to a doubleheader), necessarily. It’s just schedules. Timing, how that all works. Obviously our season ended last week. That’s something we could look at down the road, how it could fit.”

Frye also stressed that the Roval wouldn’t be the only option for a doubleheader.

Richmond, Texas and Indianapolis are other tracks that are raced by both IndyCar and NASCAR, and Newgarden certainly seems open to trying any of them.

“I think it would be really cool for the fans without a doubt,” Newgarden said. “Why would you not want to have that doubled up on a weekend? They’re just both great championships.

“I respect these guys so much, and I love keeping in touch with what they’re doing, so having a little closer access to them and vice versa for us, I think it would be a win-win for everybody.”