CONCORD, N.C. - NASCAR says that damage to the right front of Kyle Larson's car contributed to it getting airborne on the final lap of last month's Cup race at Talladega Superspeedway.
NASCAR does not plan to make any changes to the cars based on this incident.
Larson was uninjured in the incident that saw his No. 42 Chevrolet roll multiple times after contact from William Byron's car. The accident started when David Ragan's car forced Byron into the wall. Byron's car shot across the track and hit Larson's car on the right side. Larson skidded toward the inside wall, his car getting airborne.
John Probst, NASCAR Senior Vice President of Racing Innovation, estimated that Larson's car was going 180 mph when it became airborne.
Probst stated Saturday that wind tunnel testing with the wicker on the rear spoiler before the Talladega weekend showed that lift-off speed for a car should have been 250 mph.
The difference in that speed and how fast Larson's car was going before going airborne was due to the damage to the right front fender of Larson's car.
"(NASCAR) engineers … created a model that simulated that damage to the rear of the right front wheel opening," Probst said. "The results of that effectively showed us that when they had that damage, there is about a 70 mph reduction in the liftoff speed, which kind of put us in the 180-190 mph range. Our conclusion is the reason the car got off the ground is from the contact with (Byron's) car that led to the spin to the right."
The right rear wheel of Larson's car appeared to be the first wheel to lose traction with the track as Larson skidded toward the inside wall on the backstretch at Talladega. Even with the roof and hood flaps deploying, air packed underneath the car and turned the right side up to where the underbody was visible as the car hit the wall nose first.
NASCAR's research include studying replays of the accident, information from the car's incident data recorder and dozens of computer simulations. Probst estimated five people from NASCAR spent "several days" examining the cause of the accident.
Probst said that teams will be told of the results of his incident in a competition meeting Wednesday.