Teams and drivers competing in this year's IZOD IndyCar Series championship are heading to Florida for the first race of the year, the Honda Grand Prix of St Petersburg on Sunday afternoon.

There will be 25 drivers competing at St Pete this weekend, with the official entry list confirming that Brazil's Ana Beatriz will be taking the second Dale Coyne Racing seat alongside the team's returning driver Justin Wilson.

The 28-year-old tested for three out of the four sessions at Barber Motorsports Park earlier this month and had been thought to be in line to take the #18 car for all this season's oval events, plus a road course outing at her home event in Sao Paulo at the start of May.

There was speculation that for the rest of the street and road course events of 2013 Justin Wilson could be joined by his brother Stefan, a leading competitor in last year's Firestone Indy Lights championship. However, it seems that the necessary sponsorship deals haven't come together in time, at least for the season-opener this weekend, which means that Beatriz will be at the wheel.

Beatriz last competed at St Petersburg in 2011 with Dreyer & Reinbold Racing, finishing 11th on the 1.8-mile, 14-turn temporary circuit as a series rookie that season.

There's only rookie listed on the entry lists this year for the first race of the season, with Indy Lights champion Tristan Vautier taking the wheel of the #55 Schmidt Peterson Motorsports car. He won the Indy Lights race at the venue last year, and the Frenchman should attract some local support by virtue of carrying sponsorship from the Florida Lottery this weekend.

Last year's race was won by Helio Castroneves, who memorably scaled the catchfence afterwards to salute the street sign reading 'Dan Wheldon Way' in memory of the two-time Indy 500 champion who lost his life in an accident in the 2011 season finale at Las Vegas.

"It was just really great, great to remember him the way he lived and not what happened the year before," said Castroneves, recalling the event. This year he and the other IndyCar drivers will attend the unveiling of a permanent Wheldon memorial and victory circle monument on Friday morning.

Ahead of the first race of the season, the IndyCar organisers confirmed changes to the way that push-to-pass will be used in 2013, as the series seeks to standardise the use of the overtake boost button between road, street and oval events.

Push-to-pass gives the engines a turbocharger boost from 21.7 Psi to 23.2 Psi and an additional 200RPM. There will now be only 10 activations of push-to-pass per race, with the maximum time the boost lasts varying between 15 and 20 seconds depending on the nature of the circuit, or until the driver lets up on the throttle.

Organisers confirmed that there would be no delay in activation this season, and no refresh time before the next use - but also no way of cancelling it once the steering wheel button is depressed.

"If the driver chooses to use one, they can't cancel it. It's use it or lose it," explained IndyCar's vice president of technology, Will Phillips. "That in itself makes it more difficult to choose to use as a defense mechanism rather than as an overtaking opportunity.

"You'll have to be careful because there are only 10 opportunities to use it during a race," he added. "The length of each push of the button should cover the longest straight - if that's where they choose to use it - of each circuit."

This season will also see a new safety standard for drivers' helmets in the series. Under the latest rules, all IndyCar and Indy Lights drivers will be required to wear helmets that meet or exceed the new FIA 8860-2010 specification inttoduced in the wake of Felipe Massa's head injury sustained at the F1 Hungarian Grand Prix in 2009.

"The 8860 helmets provide the drivers more penetration resistance because of the penetration specification that requires a thicker carbon fibre shell," explained IndyCar's director of engineering Jeff Horton. "Because we race open-wheel cars, debris on racetrack is a potential projectile."

The first event of the 19-race 2013 calendar gets underway with two practice sessions on Friday, followed by a final practice opportunity on Saturday morning before qualifying in the afternoon.

The drivers get one last shakedown opportunity in Sunday morning warm-up before the race which is scheduled to start at 12.40pm local time, 4.40pm GMT. The race will be aired live by NBC Sports in the US, and by ESPN in the UK.

Honda Grand Prix of St Petersburg - Entry List
#1 Ryan Hunter-Reay Chevrolet Andretti Autosport #3 Helio Castroneves Chevrolet Team Penske #4 JR Hildebrand Chevrolet Panther Racing #5 EJ Viso Chevrolet Team Venezuela/Andretti Autosport/HVM #6 Sebastian Saavedra Chevrolet Dragon Racing #7 Sebastien Bourdais Chevrolet Dragon Racing #9 Scott Dixon Honda Target Chip Ganassi Racing #10 Dario Franchitti Honda Target Chip Ganassi Racing #11 Tony Kanaan Chevrolet KV Racing T echnology #12 Will Power Chevrolet Team Penske #14 Takuma Sato Honda A.J. Foyt Enterprises #15 Graham Rahal Honda Rahal Letterman Lanigan Racing #16 James Jakes Honda Rahal Letterman Lanigan Racing #18 Ana Beatriz Honda Dale Coyne Racing #19 Justin Wilson Honda Dale Coyne Racing #20 Ed Carpenter Chevrolet Ed Carpenter Racing #22 Oriol Servia Chevrolet Panther DRR #25 Marco Andretti Chevrolet Andretti Autosport #27 James Hinchcliffe Chevrolet Andretti Autosport #55 Tristan Vautier * Honda Schmidt Peterson Motorsports #67 Josef Newgarden Honda Sarah Fisher Hartman Racing #77 Simon Pagenaud Honda Schmidt-Hamilton Motorsports #78 Simona de Silvestro Chevrolet KV Racing Technology #83 Charlie Kimball Honda Novo Nordisk Chip Ganassi Racing #98 Alex Tagliani Honda Bryan Herta Autosport w/Curb-Agajanian

* denotes IZOD IndyCar Series rookie