Three drivers who will be aiming to start the Indianapolis 500 for the first time in 2013 were on track on Wednesday to get a head start on getting used to oval racing by spending a day at Texas Motor Speedway.

AJ Allmendinger, Tristan Vautier and Carlos Munoz will all need to pass rookie orientation ahead of the start of May's Indy 500 build-up, and were keen to get an early feel for ovals with as much time as possible this week.

Schmidt-Peterson Motorsport's Tristan Vautier impressed at last weekend's season opener at St Peterburg, at least until his mid-race retirement for an exhaust failure; and he also has oval racing experience from winning the 2012 Firestone Indy Lights championship. But even so, the Frenchman admits that oval racing in an IZOD IndyCar Series DW12 is a whole new ballgame.

"Everything happens to you faster, but I think it feels that way when it's your first time in a new car on a new track until your brain gets used to it," he said while getting up to speed at Texas this week.

NASCAR Sprint Cup driver Allmendinger is also no stranger to racing on ovals, but it's a very different style of racing in a stock car to the open-wheel IndyCars. And Allmendinger's pre-NASCAR experience in the Champ Car World Series seven years ago was also little help preparing him, he admitted.

"People assume back when I raced Champ Cars I did a lot of ovals, but I really only did Milwaukee so this is brand new for me," Allmendinger said. "I do have a little bit of track knowledge of knowing what the track does, but it's still a lot different.

"There's a lot of work I've got to do still, just to feel comfortable," he told the Associated Press at Texas. "Feeling like I'm more on top of the car than the car is driving me is something I'm still fighting a lot ... It all feels like I'm a fish out of water, trying to figure out how to get around."

Allmendinger lost his regular NASCAR race seat with Penske Racing last season after failing a random drug test, but team owner Roger Penske stood by the 31-year-old Californian and tempted him back to open-wheel racing with a shot at the Indy 500. He'll also compete in the Honda Indy Grand Prix of Alabama at Barber Motorsports Park next weekend as part of his preparations.

"There's a lot of pressure there, and I put a lot of it on myself," he admitted. "I don't want to go out there and waste anybody's time, and waste Roger's money."

Vautier and Allmendinger were joined at Texas by 21-year-old Firestone Indy Lights racer Carlos Munoz, who has been handed a seat to attempt the Indy 500 by Andretti Autosports.

More experienced hands taking the opportunity to test at Texas - which hosts the eighth round of the 19-race 2013 IndyCar season on June 8 - included Vautier's team mate and compatriot Simon Pagenaud, team owner-driver Ed Carpenter, AJ Foyt's Takuma Sato, and Rahal Letterman Lanigan duo Graham Rahal and James Jakes.

Having more cars on track was a help for the rookies, explained Vautier, especially preparing for the actual Firestone 550 race that he will be competing in two weeks after the Indy 500.

"The challenge coming back here will be all the things you have to do with other people on the track," he said. "The car can react differently from lap to lap by the way it moves around, so that was helpful in general.

"There's lots of grip and you can really feel the compression in the corners, and with the wind it was pretty tricky," he added. "It might be even trickier in June when we come back because it will be significantly warmer."

While Vautier will definitely be competing here in June, Munoz is unlikely to; and the jury is still out on whether Allmendinger will be tempted to stay for a longer stint back in open wheel racing or whether he'll go back to focussing on NASCAR after participating in the greatest spectacle in motorsport.

The formal Rookie Orientation Program itself will be held on April 11 at Indianapolis Motor Speedway, which is a 2.5-mile circuit unique in motor racing and very different in characteristics from the high-banked 1.5-mile Texas circuit.

All drivers who have not recently competed in the Indy 500 must successfully complete ROP before being allowed to participate in qualifying, in which only the top 33 cars make it into the actual 97th running of the Indianapolis 500 on May 26.