INDIANAPOLIS -- The Indianapolis 500 will be run for the 96th time today, but several things will be different about the venerable race this year.
All the drivers are using a new car that's untested in 500 miles of race conditions at the 2.5-mile Indianapolis Motor Speedway. The car has enhanced safety features and there are multiple manufacturers providing engines, versus only one engine maker before.
Danica Patrick, having moved to NASCAR, isn't here for the first time in eight years.
And memories of another driver, Dan Wheldon, will weigh heavily throughout the race. Wheldon won his second Indy 500 a year ago, then was killed in October in a racing crash in Las Vegas.
Two perennial favorites, Dario Franchitti and Scott Dixon of the Chip Ganassi Racing team -- who have three Indy 500 wins between them -- are struggling to find speed and will start deep in the 33-car field.
Even the pre-race ceremonies will be slightly different. Jim Nabors, who has sung "Back Home Again in Indiana" here 33 times since 1972, will miss this year's race due to heart-valve surgery. So a recording of his rendition will be played.
And this might be the hottest Indy 500 in history. The record for the race was 92 degrees in 1937, but today's forecast called for a high of 94 as a heat wave grips the Midwest. Extreme heat makes the track slippery, drivers say, and they have to be careful to be properly hydrated during the race.
Then again, the unexpected is not uncommon at the Memorial Day weekend classic, which typically draws more than 200,000 spectators.
Last year, for instance, rookie J.R. Hildebrand of Sausalito appeared to have the race won until he inexplicably hit the wall on the last turn of the last lap, enabling a stunned Wheldon to sweep by for the victory.
This year, "anything can happen, really, with the new cars and the new engines," said Tony Kanaan, the 2004 IndyCar champion who starts eighth Sunday.
Graham Rahal, who starts 12th, agreed.
"The biggest question is, what (kind of race) are we going to have?" said Rahal, whose father Bobby won the race in 1986. The younger Rahal said the uncertainties include how well the new cars handle, the durability of their engines and other unknowns. "You'd think I'd have that figured out by now. I don't think anybody really knows."
Drivers for two teams -- Team Penske and Andretti Autosport -- appear to have an edge, having taken the top six positions in qualifying.
Penske's Ryan Briscoe won the pole with an average speed of 226.484 mph.
Andretti's James Hinchliffe and Ryan Hunter-Reay will start second and third, respectively, alongside Briscoe under the Indy 500's unique format of starting the cars in 11 rows of three cars each.
In the second row are Marco Andretti, Penske's Will Power and his teammate Helio Castroneves, a three-time winner who is trying to join A.J. Foyt, Al Unser Sr. and Rick Mears as the only drivers to win the race four times. No driver has won it five times.
Castroneves won the season's opening race in St. Petersburg, Fla., and Power won the next three in Birmingham, Ala., Long Beach and Sao Paulo, Brazil.
But all four races were on street or curvy road courses. The Indy 500 is the series' first oval race of the year and thus a major test of the IndyCar series' new car.