Sharp paces opening day of practice

Sharp's lap, one of just nine in his back-up car, was just a tick better than Helio Castroneves' best lap of 228.088mph before rain cut two and a half hours off the session.

"Everybody got some drafting help," Sharp said. "Obviously I did. I don't know how much you can take from a day like today, but it's a good place to start."

Toyota posted the three fastest laps of the day - Sharp's, Castroneves' and Tora Takagi's 227.884. Honda and Andretti Green Racing had the next two spots - Dan Wheldon's 227.716 and Michael Andretti's 227.461. Toyota had eight of the 10 fastest laps of the day; Sharp had two of those eight - his primary car was clocked at 226.845 mph.

"That was not the car we were supposed to be testing," Sharp said. "We just wanted to run it one time, baseline it and go to the other car. I don't know which one is our race car right now. It's supposed to be the primary car, but we'll see."

Mo Nunn Racing had the best overall team performance of the session, with laps by three drivers among the top eight speeds posted Sunday. Takagi's Panoz G Force-Toyota led the way, while Felipe Giaffone was seventh-fastest and 49-year-old Arie Luyendyk was eighth-fastest.

Once again, the Chevrolet engine struggled against the Japanese manufacturers. The fastest Chevy-powered car -Sam Hornish's Pennzoil Panther Dallara - was 11th-fastest at 225.949 mph.

Castroneves and team-mate Gil de Ferran are trying to decide between the Dallara and G Force chassis. Castroneves drove the Dallara on Sunday, while de Ferran - in his first time in a car after missing six weeks because of injuries - drove the G Force.

"Hopefully by Thursday we'll know what we're going to use," Castroneves said. "I do have a lot of input into it, but I have a lot of good engineers giving me input on that, too. Right now, it's so difficult to now. Both cars are very competitive."

A total of 29 cars driven by 24 drivers recorded 697 total laps during the three-hour session. Among them was Robby Gordon, who finished fourth in the rain-shortened Pontiac Excitement 400 on Saturday night at Richmond.

Gordon, who will replace injured Dario Franchitti for AGR, will go back and forth between Winston Cup races and Indy during the month, eventually competing in the Indy 500 and Coca-Cola 600 in Charlotte on May 25. Gordon did just 10 laps Sunday in Franchitti's backup car, with a fast lap of 220.636 mph. Practice will continue throughout the week, culminated by Saturday's pole qualifying.