The Ferrari F2004 is one of the most successful cars in F1 history

The car will be unveiled in February but Michael Schumacher and Rubens Barrichello will drive a modified version of the 2004 car for four races.

"We're going to start the championship with the F2004B to a specification which takes into account the new regulations," said team boss Jean Todt.

"Considering the new rules, one power unit for two Grands Prix, we want to do two sequences of two Grands Prix."

Ferrari dominated last year, winning 15 of the 18 races.

They will be going for a seventh successive constructors' title in 2005, while Schumacher has an eighth drivers' crown in his sights.

It's going to be important to have an extremely competitive and reliable car Ferrari team boss Jean Todt

The new regulations have doubled the life span of a Formula One engine in an attempt to cut costs and reduce speeds, forcing teams to use the same ones for two successive races.

Todt predicted an "extremely difficult" championship ahead, given the rule changes on engines, tyres and aerodynamics.

There will be an unprecedented 19 races this year, with several back-to-back.

"Clearly, this will require continuous and intense effort on our part, but this is true for everyone," said Todt.

"It's going to be important to have an extremely competitive and reliable car because should one have problems the possibility of managing these problems in such short intervals is going to make our lives difficult."

Ferrari will have to modify their F2004 to comply with new regulations that restrict aerodynamics.

But using that car for the first few races has the benefit of ensuring they do not risk poor reliability with a relatively unproven car early in the season.

It is a tactic Ferrari have employed with great success in recent years, particularly in 2002.

All their main rivals are planning to race brand new cars from the start of the season, which begins in Australia on 6 March.

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