CONCORD, N.C. — NASCAR’s top division will race without engine restrictor plates at Daytona and Talladega next season for the first time in 32 years, instead relying on a smaller tapered spacer and increased aerodynamic downforce to reduce speeds at the circuit’s largest speedways.

The total effect of the smaller spacer, larger spoilers and splitters, plus aero ducts is expected to reduce horsepower and increase drag to replicate the current brand of racing in the patented tightly woven packs at those two superspeedways.

RELATED: Explaining 2019 rules

Current restrictor-plate engines make an estimated 410 horsepower. Tuesday’s rules increase the target horsepower to 550, but the aerodynamic devices are expected to offset that potential gain in the speed column. The change will not be in place for the 2019 Daytona 500, instead taking effect April 28 at Talladega.

“We wanted to keep the Daytona 500 as-is,” said Steve O’Donnell, NASCAR Executive Vice President and Chief Racing Development Officer. “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 has used restrictor plates to decrease speeds at 2.5-mile Daytona International Speedway and 2.66-mile Talladega Superspeedway in every race since Bobby Allison’s airborne crash into the Talladega catch-fencing in May 1987. Bill Elliott’s qualifying speed for that event was a record 212.809 mph. By contrast, the pole-winning lap for the most recent Talladega race was 194.448 mph, posted by Kevin Harvick in April.

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Restrictor plates and tapered spacers have common purposes. Both restrict the passage of air through the engine to reduce horsepower, but the tapered spacer’s funnel-shaped design allows for a slightly more efficient flow and throttle response.

O’Donnell said that discussions with engine builders were critical in the development of the forthcoming rules package, especially with the considerations made for Daytona and Talladega, but added that competition officials are positioned to make slight alterations if necessary. NASCAR did so at Talladega last May, opting for a smaller restrictor plate to curtail horsepower and speed after Jamie McMurray’s car left the ground in a crash during practice.

“I think in terms of the racing and speeds, they’ll be very similar,” O’Donnell said of the contrast between the 2019 rules package and the current restrictor-plate setup. “We’ve got the ability obviously to dial that up or down as necessary, but we’ll certainly keep an eye on that as we roll out in practice as we always do, but to have the ability to make some tweaks if we needed to once that race weekend starts.”

CONCORD, N.C. — NASCAR took the step of launching its 2019 rules package Tuesday for the Monster Energy Series. But it’s the next stages that may bring even more significant change.

Steve O’Donnell, NASCAR Executive Vice President and Chief Racing Development Officer, says the sanctioning body continues to have talks with new manufacturers to compete alongside Chevrolet, Ford and Toyota, with a 550-horsepower target providing a more attractive entry point for automakers over the current 750-horsepower baseline. O’Donnell also indicated that progress continues to be made toward a seventh-generation stock car, the next evolutionary step for the vehicles in NASCAR’s premier series.

RELATED: Explaining 2019 rules

The 2019 rules package — featuring aerodynamic and engine changes intended to heighten the competition level next season — is designed to be a bridge to both of those developments, O’Donnell says.

“I think if you look at our current partners, it’s important to speak with them first and I think they’re very happy with where we are in the sport, but we always want to grow,” O’Donnell said. “And when we talk about growth, that means being more relevant, potentially introducing more technology into the sport, especially around the engine. As we’ve had discussions with new OEMs (original equipment manufacturers), the direction we’re going in for next year’s rules package really opens up a variety of options for us to bring in new OEMs, to have our current OEMs potentially accept a new direction.

“So a lot of thought went into this that this isn’t just a 2019 rules package, it’s something that we believe really sets us up for the future — not only for our current partners, but growing the sport, which hopefully leads to more healthy ownership as well where we can bring some new OEMs in.”

NASCAR introduced the current sixth-generation car — labeled “Gen-6” — in the 2013 season, taking competition and safety cues from the previous model while strengthening the brand identity for the three participating automakers. O’Donnell indicated that a Gen-7 car could further define those manufacturer distinctions, all while exploring long-term technological progress in a closer-to-stock vehicle.

“I think when you look at the next-gen vehicle, if you look at what people are driving on the street today in terms of horsepower numbers and different relevancy options, in terms of electrification or partial electrification, all those things become an option for you,” O’Donnell said. “Do I ever think we’ll be a hybrid racing series? No, but this allows for some tweaks to the engine package down the road if we wanted to when we race around this horsepower, so it gives us a real look not only to what we believe will be better racing than we’ve produced in the past but it also opens it up to new OEMs, opens it up to new technologies and really puts us on a great growth path for the future.”