Two-time Formula One champion Fernando Alonso says he knows what he has to do in the Brazilian Grand Prix to wrest this year's title from Sebastian Vettel, the current points leader.

How each fares in Sunday's final race of the 2012 season will determine whether the 31-year-old Spaniard or the 25-year-old German becomes the youngest driver to win three world crowns.

"We know we have to score 14 points more than Vettel for the Championship and not lose the same number to McLaren to maintain our second place in the Constructors," Alonso said in a statement issued by his Ferrari team.

"Our targets are clear, but also difficult to achieve," he said.

"It was very hot out on the circuit today and, especially this afternoon, the track temperatures were well above normal, even for this circuit. We have not yet found the ideal balance on the car, so there is still a lot of work to be done with the engineers going into the rest of the weekend," the Spanish driver said.

The track in Sao Paulo is where Alonso celebrated his F1 titles in 2005 and 2006, but he has never won the Brazilian Grand Prix.

Vettel triumphed in the 2010 edition of the event. EFE