CONCORD, N.C. – Tuesday afternoon, NASCAR announced two baseline rules packages for the 2019 NASCAR Cup Series season.

The packages will be tailored by track type to deliver even more exciting, side-by-side racing.

“It’s really been over a two-year process, working with the race teams, the OEMs, specifically the engine builders and probably the most collaborative effort we’ve had across all the industry stakeholders, including the drivers, to get to this package,” Steve O’Donnell, NASCAR executive vice president and chief racing development officer, told “For us, it’s really a focus on getting back to a true focus on the drivers and what NASCAR is all about – close side-by-side racing and trying to deliver more of that.”

The aerodynamic elements of the 2019 rules package include an eight-inch by 61-inch spoiler, a splitter with a two-inch overhang and 10.5-inch wings at the ends near the tires, and a radiator pan that is 37 inches wide in front tapered to 31 inches with vertical fences.

Those changes will be in place for every race next season in order to add downforce and stabilize handling.

When the rules were announced, Chase Elliott took to Twitter to share his reaction.

"New challenges and opportunities are ahead for all of us drivers and teams, I look forward to embracing it personally," he tweeted. "As long as the best still rise to the top, I support it."

Part of the new package is a tapered spacer that will measure either 1.17 inches or 0.922 inches depending on the track. The smaller tapered spacer is designed to reduce engine horsepower to a target of 550 horsepower, down from the current 750. It will be used at oval tracks larger than one mile long. The larger tapered spacer will be used at short tracks and road courses.

Additionally, aero ducts will be used at a majority of oval tracks larger than one mile in length.

The smaller tapered spacer and aero ducts will both be in effect for 17 races next season, while five races – Atlanta, Darlington, Homestead and both Pocono events – will be run with the smaller spacer but without the aero ducts.

“From an aero standpoint, I think you’ll see a pretty similar package to what we had in the (2018 NASCAR) All-Star Race and what we’ve seen in the Xfinity Series,” O’Donnell said. “Where we looked to make a little bit of a change was around the horsepower and that was, after discussions with the drivers, discussions with the engine builders as well, as what would be something that would produce a little more on-throttle time and have a good relationship with the aero package that we put together. So, we made a tweak to that.”

Also of note, races at both Daytona International Speedway and Talladega Superspeedway will be run without restrictor plates for the first time since 1987. The exception is the 2019 Daytona 500, which will be run with traditional restrictor-plate rules.

“We wanted to keep the Daytona 500 as-is,” O’Donnell said. “There was a lot of engine inventory already out there. Teams had already begun preparing for the 500, so we wanted to hold the line there for 2019. And then as we started the season again from a superspeedway standpoint at Talladega, going to that 550 (horsepower) tapered spacer, we think will produce exactly what we’ve seen in the past, the side-by-side racing that fans love. So, certainly we’ll learn some things along the way, but believe you’ll see very similar styles of racing at those tracks.”

NASCAR also announced that there will be a 25 percent reduction in testing in 2019. There will be three organizational tests – down from four – and three teams at each Goodyear tire test – also down from four.

The use of sealed engines will also be expanded next season, increasing to three long-block engine seals in points races in addition to the 13 short-block seals introduced in 2018.

The green flag for next year’s Daytona 500 is on Feb. 17, 2019. But before that, 12 NASCAR Cup Series competitors are still in the hunt for the 2018 championship in the playoffs, including two Hendrick Motorsports teammates – Elliott and Alex Bowman.

The Round of 12 in this year’s playoffs begins next weekend at Dover International Speedway. The race is scheduled for 2 p.m. ET on Sunday, Oct. 7, and will be broadcast on NBCSN, MRN and SiriusXM NASCAR Radio.