INDIANAPOLIS -- Two IZOD IndyCar Series practice sessions June 22 totaling 90 minutes will play integral roles in setting the starting grid for the Iowa Corn Indy 250.

As announced by INDYCAR in mid-February, three heat races of 30 laps each will replace single-car qualifications for the June 23 race under the lights on the .875-mile Iowa Speedway oval.

According to Rule 8.5 of the IZOD IndyCar Series rulebook, groups for the 6:15 p.m. (local) qualifications will be determined by combined practice session times.

Race 1 will consist of the even-numbered positions, starting with the 10th-quickest practice time overall, and determine the even-numbered positions in the starting field from 10th down.

Race 2 will consist of the odd-numbered positions, starting with the ninth-quickest practice time overall, and determine the odd-numbered positions in the starting field from 9th down.

Race 3 will consist of drivers ranked one through eight by combined practice times. Results of Race 3 will determine the top-eight starting positions with the winner taking the pole position for the Iowa Corn Indy 250.

INDYCAR president of competition Beaux Barfield said the qualifying procedure was introduced for this event only as an experiment to add excitement. Single-car qualifications with the cumulative time of two laps will be held at the Milwaukee Mile on June 15 and Auto Club Speedway on Sept. 14.

The new Iowa oval qualifying procedure will complement the three rounds of qualifications held on road/street courses, culminating in the Firestone Fast Six.

"The build-up we presently have for the Firestone Fast Six has that excitement and we wanted to do something similar for the oval events," Barfield said. "It's going back to the heritage of short-track races."

Double-file restarts also will be utilized at Iowa Speedway, which has played host to the IZOD IndyCar Series since its opening in 2007. Marco Andretti of Andretti Autosport won the 2011 race.

"We've had a lot of firsts at Iowa Speedway with INDYCAR and the mini-races are another first," said Stan Clement, president of Iowa Speedway. "With the new car and the heat races, fans who attend the Iowa Corn Indy 250 weekend will get racing on both days."