SAO PAULO, Brazil - Rubens Barrichello will begin his first full season in Brazilian stock-car racing on Sunday after more than two decades of competing in Formula 1 around the world.He's back home after ending his F1 career two years earlier and failing to secure a seat for a second season of IndyCar. The now 40-year-old said he wasn't ready to retire so decided to join the local series after driving a few races as a guest in 2012."Everyone is entitled to a re-start," he told Globo TV. "I'm giving myself this opportunity. I had a new beginning in the US, now I'm having another one in Brazil, closer to my family."'STILL LEARNING THE CAR'He doesn't dismiss racing in events such as the 24 Hours of Le Mans or the 24 Hours of Daytona in the future but is not thinking about leaving the country again to race in other series.Barrichello struggled in his three stock-car races in 2012, finishing no better than 22nd, but was fastest in a practice session ahead of the 2013 season opener scheduled for Sunday (March 3) and will start 14th in the 34-car grid."I have a lot of experience at Interlagos but in a different type of car," Barrichello said. "I'm still getting to know this car, I still feel like a rookie but hope I'll be competitive."My main opponent is still the car. I think today I'd still be more adapted to an F1 car than I am to the stock car but this is not an excuse, my future now is here, I have to make it work."Last year he complained about all the bumping and banging in the series, saying he felt he needed a bullet-proof vest. He was 22nd in his first race, retired in his second and was 22nd again in the 2012 season finale at Interlagos.RECORD TIME IN F1Barrichello's best finish in IndyCar in 2012s fourth in Sonoma, California. He followed that with fifth in Baltimore but ended the year 12th in the Drivers' championship.The Brazilian raced for a record 19 years in F1, finishing second in the Drivers' championship in 2002 and 2004 for Ferrari, both times behind seven-times champion Michael Schumacher.He won 11 F1 races and holds the series' record for most starts - 322.The Brazil stock-car season will have 12 races through 2013, finishing on December 15 at Interlagos.