NOON UPDATE

Team Penske's Helio Castroneves led the 10 drivers participating in Monday's IndyCar Spring Training session at Sebring's short course, turning a 52.94-second lap just before the lunch break to top Andretti Autosport's Ryan Hunter-Reay, who sat out for the first half of the morning. Once on track, Hunter-Reay quickly registered a 53.10-second tour around the 1.8-mile, 10-turn circuit.

Helio Castroneves went P1 just before teams broke for lunch on Monday. Check back in a few hours for an update once the running concludes. (Photo: Marshall Pruett)

"I'm focused on the car and just feeling everything," Castroneves told SPEED.com. "I'm not even focused on the times right now. At the end of the day, when we go to the tracks that we race on, you have to learn what you need for those places, not just to be fast here, so we're encouraged but not looking at the times."

Team Penske's Will Power had multiple offs Monday morning on the way to setting the third-fastest lap at 53.11, followed by Ryan Briscoe, the final member of the Penske trio in fourth with a 53.33-second lap.

Briscoe executed a harmless spin which brought out a brief red flag, but had no other issues.

Andretti's James Hinchcliffe managed a 53.64-second lap which was good enough for fifth, but the Canadian's body language indicated he thought a lot more speed could be found in the afternoon.

Dale Coyne Racing's Justin Wilson followed Hinch with a 53.78-second lap, Marco Andretti, like RHR, waited out the first half of the morning and went seventh-fastest with a 53.88-second run.

Coyne's James Jakes, making his second pre-season outing, turned a 54.51-second lap and Simona de Silvestro, driving the lone Lotus-powered car, closed out the running order in her HVM Racing entry with a 54.56-second lap.

An 11th car was listed for the Monday-Tuesday portion of the test, with Dragon Racing's Katherine Legge expected to appear on Tuesday, but at present, the team's cars are in the paddock without engines.

Her teammate, Sebastien Bourdais, is scheduled to test during the Thursday-Friday segment of the event, while reported contract issues between the team and the British marque continue to be discussed.

Times were down significantly to the high 51-second laps turned two weeks ago, but much of that can be attributed to tires.

While most tests prior to Spring Training were conducted using a wide variety of Firestone compounds, a representative told SPEED.com that all cars will use just one spec this week--the harder primary tires that will be employed for at least the first five street races of 2012.

Marshall Pruett is SPEED.com's Auto Racing Editor, covering IndyCar and sports cars. He also contributes to Road & Track and Racecar Engineering. Follow him @MarshallPruett on Twitter.