INDIANAPOLIS (AP) — Run, NASCAR, don’t walk, back to the drawing board to figure out how to liven up racing. The rules package used for the Brickyard 400 was a failure no matter how the race is dissected.

The high-drag aerodynamic package was supposed to improve passing at Indianapolis Motor Speedway. It was clear from the first practice session for one of the most important races of the season that NASCAR did not meet its desired result.

Yet nothing was changed before Sunday’s race, which featured just 16 lead changes. In fairness, that was one more lead change than last year’s race at the Brickyard, but it was still the second fewest since 2011. NASCAR’s statistics also showed that green-flag passes were down by 587 from last year.

When the race finally ended, the drivers were less than complimentary of the event. Kevin Harvick called the rules package “a huge science project,” and Matt Kenseth called it “terrible.”

Even race winner Kyle Busch had issues in traffic.

“Whether you were behind a guy or behind a group of cars, you were horrible,” he said. “It was just absolutely so hard to handle in traffic. You don’t want to feel like you’re going off into the corner and you’re going to crash every time.”

Behind the scenes, teams fumed all weekend that Gene Stefanyshyn, NASCAR’s vice president of racing development and the architect for the Indianapolis aero package, was on a family vacation and not even at Indy. The reality, though, is that his presence wouldn’t have changed the outcome.

NASCAR has struggled valiantly to create a rules package that produces dramatic racing. If there was a way to bottle what IndyCar does on ovals, NASCAR would buy it in truckloads. But the route NASCAR followed has failed, and the series is stubbornly staying the course despite the results.

Series officials listened to what the drivers wanted and used a low-downforce package at Kentucky. Maybe it was a better race, maybe it wasn’t. But most of the drivers raved about the final product and almost every measurable statistic showed the competition was better.

Two days later, NASCAR Chairman Brian France threw cold water all over Kentucky by downplaying any noted improvement. Like his employees entrusted to fix the racing, he looked forward to Indianapolis and the package designed by NASCAR.

France made it clear: He wants pack racing, he wants cars making slingshot passes and he wants excitement.

He didn’t get it Sunday.

NASCAR vice chairman Mike Helton on Monday said series officials will take some time to digest the race and the rules package, which is also scheduled to be used Aug. 16 at Michigan.

“We can absorb all the of the science and the data we collect, including talking to the industry, the drivers, the crew members and the competition departments of the teams and the car owners,” Helton said on SiriusXM NASCAR Radio. “That’s part of the reason we created this specific package for Indianapolis – to see the characteristics of it, knowing that there are a lot of personalities in the garage area that have different opinions . but it’s on NASCAR to come up with the one that we put in front of the fans on each individual racetrack each weekend. So, we’ll take time.”

Helton is correct that drivers often want different things from the race car. Although many raved about the low-downforce package at Kentucky, that setup requires talent. Take away too much downforce and the car could be very difficult to drive for those near the back of the field.

And, in France’s defense, the Kentucky race was hardly the best in NASCAR history. It was better, but it wasn’t one for the ages.

The Kentucky package will be used again at Darlington Raceway for the Southern 500, one of NASCAR’s crown jewel events. If that race is indeed improved, and drivers again walk away pleased with the product, NASCAR will have to take a hard look at giving the drivers what they want on a regular basis.

Right now, the sentiment is that NASCAR picked a bad rules package for 2015 and has double-downed on figuring out a version that will work. It didn’t work at Indianapolis, and NASCAR needs a new plan.

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