Being the local hero will make his first IZOD IndyCar Series in Brazil race a memorable event for Rubens Barrichello - but it's no cure for the issues that stand in the way of real racing success in his new post-F1 career, the driver admits.

"My biggest problem is not knowing the tracks," Barrichello told the Associated Press ahead of this weekend's Sao Paulo Indy 300 street race. "That's going to be the case again here in Brazil ... The difficulties will be the same as before."

Barrichello acknowledged that being on home ground and having such massive support from the fans will be a mental boost for him, and that it will heighten his desire to do well for the cheering crowds. But he insists that it's no magic remedy for the problems he's having as he attempts to transition from F1 to IndyCar in 2012.

"I'm still not 100 per cent comfortable with the car," he said. "It's completely different from what I used to drive in F1."

The lack of available testing time away from race weekends has been a factor, although at least the IndyCar Series organisers have now granted him extra test time by categorising him as a 'rookie' for tracks where he has not previously run, such as this weekend's Sao Paulo temporary street circuit.

The KV Racing Technology team is also doing what it can to support Barrichello during the transition, recently hiring former Andretti Autosport engineer Eddie Jones to work with the F1 veteran. Jones helped Dan Wheldon to his first Indy 500 victory in 2005.

In fact, while Barrichello's first IndyCar races might be falling behind his own high expectations, by anyone else's standards they're looking rather decent.

After technical problems dropped him to 17th at St Petersburg, he's finished the last two races in the top ten. He's currently ninth in the IZOD IndyCar Series championship standings and is ahead of both of his two experienced KV Racing team mates Tony Kanaan and EJ Viso in the points.

But for Barrichello, that's not good enough for the most experienced F1 driver in history, a veteran of 322 Grand Prix starts over a period of 19 consecutive seasons in the sport. He won't be happy until he's emulating the last high-profile transfer from F1, Nigel Mansell in the early 1990s, who won five races and the CART series title in his rookie season in the US.

"I'm always thinking positive," Barrichello insisted. "I'll be giving my best this weekend," he said, adding: "Let's just see what happens."