The sentence “NASCAR Cup Series is returning to Bristol Motor Speedway” doesn’t sound that interesting. But when you see the state of the track, you might change your mind.

That’s because NASCAR’s Tier 1 series has decided to temporarily cover the track in clay and dirt for a 250 lap race. Just what the drivers can expect the track to look like by the end of that race is kind of unknown.

Speaking to Autoweek for an extensive article that goes into more detail, Steve Swift, who has acted as project manager for the dirt conversion, said there are more unknowns than knowns.

“The Cup Series has not been on dirt in a long time, so (there was) nothing to go watch (to) see how that reacts, what that does,” Swift said.

Based on shorter-length dirt track races, though, they know that humidity, especially for a 250-lap race, will be a major concern.

“I think it comes down to making sure we’ve got enough moisture that’ll hold on, and that the dust stays mitigated,” Swift explained. “Again, I want to iterate we’ll have dust but should be able to mitigate it to where it’s not unbearable to see, and the duration is really good.”

The team has also had to fill the banking turns a bit. Dirt just won’t work on the track’s normal 30-degree banking, so the angle has been relaxed to 19 degrees. Still, though, heat, rain, the length of the race and more could all affect the outcome.

“It could rain, and it could be heavy and rough, and we’re ripping the noses off the car,” says Kyle Larson, the current Cup racer with the most success in dirt series. “Honestly, I hope it does get a little bit rough because I think that will add some characteristics to the track (and) open up some different things.”

Indeed, a number of racers will be entering other dirt events to get as much experience on the surface as possible before the March 27-28 event. Regardless of experience, though, there are concerns about whether or not the track will allow any passing once the cars beat the surface down. Swift, for one, believes things look good.

“Turns 1 and 2 should be capable of passing from what our sim data has kind of shown,” he said. “I’m not saying that it will be, because anything could happen that weekend. We don’t know. It’s the unknown, but from the simulation and design, it shows that they should be able to pass.”

Whatever happens, the unknowns of the event are attracting a lot of attention from fans, according to Clint Bowyer, a FOX Sports analyst. “I’ve been on this old road for a while,” Bowyer said. “Man, I’m ready for something new. That new is here.”