|Kahne is on the pole for the third time at Las Vegas (Getty)|
Fourteen other drivers followed to also break the previous mark, but only Kasey Kahne drove faster than the Las Vegan. Kahne went 190.456 mph to win the pole for Sunday's Kobalt Tools 400.
Busch turned in a speed of 190.040. Matt Kenseth's speed of 188.884 mph set last year was the record entering the day.
Kahne attributed the fast laps, three of which were better than 190 mph, to better racing equipment combined with an ideal surface.
"I was surprised we didn't beat the track record last week at Phoenix," Kahne said. "Same thing, just the track was a little too slick to do it. So I'd say at this point we'll probably break some records this year on tracks that are capable."
Kahne, who drives the No. 5 Chevrolet, has excelled at qualifying. He has 23 career poles, including three in Las Vegas. His first pole came at the track in 2004.
But Kahne is struggling to overcome a tough start to this season. He took strong cars to Daytona and Phoenix, but wrecked in both races to finish 29th and 34th, respectively.
"The way to dig out of that is to qualify well and run well and not make mistakes," Kahne said. "I feel like we can do that. Hopefully, Sunday will be the first day that we can put a full race together and leave Vegas with some momentum and feel good about ourselves again."
Busch, in his No. 18 Toyota, hopes qualifying is a good indication of what's to come Sunday. He won in Las Vegas in 2009, his only Sprint Cup victory at the speedway.
Las Vegas ranks only behind the Daytona 500 and Brickyard 400 on the list of races Busch most wants to win.
"Certainly, there's added pressure from myself feeling like you really want to run well in front of the hometown crowd and being able to go out there and be successful here," he said. "This is one of those places that you stack up on the win list where you want to be able to win like a Coke 600 or an all-star race."
Busch said he wasn't sure how well he would qualify after being loose in practice. He was 20th, averaging 186.303 mph over five laps, and Busch credited crew chief Dave Rogers and the team for making the proper adjustments.
"The car felt great," Busch said. "Wasn't sure it was going to be that good."
Busch's older brother Kurt qualified 12th in the No. 51 Chevy. He is coming off a 15th-place showing at Phoenix with low-funded Phoenix Racing.
"It's just neat seeing things come together this way," Kurt Busch said. "Now I'm getting more comfortable with how the car can get adjusted and what we can do in practice to make it better. The No. 51, we are still finding more speed with it."
Another Las Vegan, Brendan Gaughan, qualified 23rd in the No. 33 Chevy. He started 40th in his season debut at Phoenix but drove to a 27th-place finish.
"From last week to this week, I'm feeling like a whole different person," Gaughan said.
Scott Riggs and Robby Gordon failed to qualify.
Qualifying for today's Nationwide Series Sam's Town 300 is at 10:35 a.m. The race is at 2 p.m.
Practice 1 Results