Las Vegas will test whether NASCAR's big bet on new aerodynamic package pays off

Martin Truex Jr. rallied for a good view of Brad Keselowski’s rear bumper but couldn’t pass him in the waning laps Sunday at Atlanta Motor Speedway in a race that showed the potential benefits of NASCAR’s 2019 aerodynamic rules as well as the potential limitations.

A late-race pass for the lead could have helped NASCAR prove its 2019 aerodynamic package has merit. A margin of victory of 0.218 seconds – a much closer finish than a year ago when Kevin Harvick won by 2.69 seconds – didn’t hurt, but a wait-and-see attitude remains within the industry and the fan base.

In a sport where the leader typically has an aerodynamic advantage, NASCAR continues on a never-ending, somewhat futile, somewhat vital journey to encourage the best racing possible.

This year’s theory: Slower can be better. NASCAR has reduced air flow in the engines for all ovals more than 1.3 miles in length, cutting horsepower from 750hp to 550hp.

The worn surface at Atlanta – its last repave came in 1997 – eats into tires more than other tracks, and drivers cautioned on reading too much after that race. Passes for the lead were the most in three years but fewer than in 2015 and 2016. The number of overall quality passes (green-flag pass while in the top-15 spot) ranked ahead of 2018 but below the three previous years.

“We thought we saw a pretty entertaining race with a good battle for the lead at the end that wasn’t precipitated by a late caution,” NASCAR Chief Racing Development Officer Steve O’Donnell said after Atlanta. “That’s ultimately what you want.”

Truex, though, said he didn’t have as much confidence he could pass Keselowski in 2019 as he would have in 2018.

“If the guy in front of you is running the same line as you, if you even get near him, you’re done,” Truex said. “You can’t go anywhere. You lose all grip.”

NASCAR’s next test comes this weekend in the Pennzoil 400 at Las Vegas Motor Speedway (3:30 p.m. ET, Fox), a change Truex said would be “completely different” as drivers will run more in a pack. Vegas is one of 16 races on ovals 1.5 miles and larger where NASCAR will use aero ducts to push air out the front wheel wells in hopes the cars race more like trucks by punching a big hole in the air while also drafting to make slingshot passes.

At tracks that require more braking – road courses, ovals less than 1.5 miles and the intermediate-sized tracks of Atlanta, Pocono and Homestead – the aero ducts are converted into brake-cooling ducts.

NASCAR won’t predict how much this aero package will translate to higher television ratings and attendance. NASCAR Cup Series ratings dropped approximately 20 percent last year and the publicly traded track companies saw an overall admissions revenue drop (the figures include all NASCAR and non-NASCAR racing events) of 9 percent, according to International Speedway Corporation's annual report.

Drivers recognize those challenges and, in general, applaud NASCAR for efforts to boost interest. But they naturally doubt any change not tested on the track, and predict crazy restarts with an increase in crashes with this package.

“Drafting right on the restart is really critical and making the right lane choices and decisions and swapping lanes at the right time and kind of being able to predict all that is super, super critical,” Keselowski said. “And I think we'll see that play out over races to come.”

By reducing speeds, NASCAR potentially turns away fans who view these drivers as brave superheroes, willing to take risks that others just won’t (or can’t) do.

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The 550hp configuration for Cup, though, has a key potential upside as NASCAR hopes it helps attract new manufacturers that have more interest in building an engine toward that specification.

More downforce thanks to a rear spoiler increase from 2.375 to 8 inches tall combined with less horsepower can make cars theoretically easier to drive, a common complaint after a similar package was used for the 2018 all-star race. Prior to the 2018 playoffs, Kyle Larson quipped, "I'd like to win the last championship where a driver means something” while noting he will race whatever package NASCAR dictates.

“It just felt like a typical race,” Larson said after leading 142 laps at Atlanta. ‘I didn’t think the package made us battle for the lead any differently.” 

Fans must be able to recognize the impact of drivers in a sport where a perfectly engineered car can hide a driver’s weaknesses. If this new package equates success with driver talent, NASCAR will win big. If fans perceive it as a gimmick to create tighter racing while also making the cars slower and racing longer, NASCAR will find itself with an even bigger challenge than it already faces.

Bob Pockrass is a Fox Sports NASCAR reporter. Follow him on Twitter @bobpockrass.