It's a sweltering Carb Day at Indianapolis Motor Speedway, where the IZOD IndyCar Series competitors are preparing for Sunday's (which will be equally sweltering, we've been told) 96th Indianapolis 500. All the regular-season teams changed engines between last Sunday's end of qualifying and today and, for the Honda competitors, an update to their 2.2-liter V-6 is helping to close the gap to Chevrolet.

"We perform updates with every iteration," said Steve Eriksen, vice president of Honda Performance Development, "but we are still behind the Chevy engines. We're hoping we can get a bit more parity down the road."

The hour-long practice session for the Indy cars, between 11AM and noon had only 32 cars, not the traditional 33 who will start Sunday's race. Ana Beatrz performed a single installation lap and a leak was found at the rear of the car, which the team repaired - but not with sufficient time for the lucky 13th starter to get her No. 25 Ipiranga Dallara/Chevrolet/Firestone Indy car onto the trck for practice.

The fastest cars in this draft-fest were the Team Target (Honda) pair of Dario Franchitti (222.360 mph) and Scott Dixon (222.274). "The car is real good,"Franchitti confirmed. "It would have been nice to have had that motor for qualifying… We'll deal with the heat on Sunday but it's going to be hard work behind the wheel in those conditions, hard for the pit crew to keep their focus in that heat," he said.

Marco Andretti's Chevy was third, while Takuma Sato took his Honda-powered Indy car to fourth place. Pole man Ryan Briscoe's Chevy completed the top five roundup. Justin Wilson (Honda), Will Power (Chevy), James Hinchcliffe, Tony Kanaan and Ryan Hunter-Reay, all with Chevrolet power comprise the balance of the fastest 10 this morning.

As expected, Lotus' two teams were slowest of the bunch, Simona de Silvestro at 206.643 mph and Jean Alesi at 204.452 mph.

The 40-lap Firestone Indy Lights Freedom 100 race was a succession of qualifying laps for most of the field, punctuated by two crashes. The first involved the cars of Brandon Wagner, Oliver Webb and David Ostella; Emerson Newton-John got sideways avoiding the melee and as he slid across the track he took the nose off Dempsey's machine. Everyone was checked, cleared and released to drive, but the SAFER barrier needed some work so the race was red-flagged for quick repairs.

The second caution came on the 38th lap, with Esteban Guerrieri in the lead and winning the race, giving Sam Schmidt Motorsports its fourth consecutive Freedom 100 victory.

The 2012 IZOD Pit Stop challenge was the final competition of the day. Customarily this is a Team Penske benefit but this year it was won by Scott Dixon and Target Ganassi Racing, their first victory in the contest, giving the No. 9 crew $50,000 for their efforts.

Panther DRR's Oriol Servia made it to the finals after beating Franchitti to lots of cheers from the crowded grandstands on either side of the track. Servia had been first off the line against Dixon but the Ganassi crew aced the pit stop and that was that.

When we left the track, a sea of humanity was making its way to the golf course area next to the Speedway Museum for the Lynyrd Skynyrd Miller Lite concert.