Di Montezemolo spoke out in Bahrain, where Ferrari won their first points of 2009
By Andrew Benson
BBC Sport in Bahrain
Ferrari president Luca di Montezemolo has blamed "badly written rules" and his team's "presumptuous approach" for their continued struggles this season.
The Italian listed those among four reasons for Ferrari's lack of pace.
The others were that the Kers power-boost systems were not mandatory and that Ferrari started designing its 2009 car late due to its 2008 title battle.
"I have a big confidence in the team," he said. "I am sure that we will be back - not immediately, but very soon."
Speaking at Sunday's Bahrain Grand Prix in which Kimi Raikkonnen won the team's first points of a disastrous season after finishing sixth, Di Montezemolo said he was "totally unhappy" about Ferrari's performance, which he described as being in a "black tunnel".
We have seen very badly written rules. They are what I call grey rules, with different interpretations
"The stability of the team and confidence of the team for me since 1992 was my main goal and I will continue," he said as he contemplated Ferrari's worst start to a season since 1981, vowing to revive the team.
"This team is exactly the same team that was very close, crossed the line not 20 years ago but a few months ago winning the championship, so there is no problem," added Montezemelo, referring to the team's success in winning the constructors' crown in 2008.
"When I know the reason I am confident, and when I don't know the reason I am worried.
"I know the reason, my people know the reason - and they are fully committed, so I am very confident. But then I am very upset for other reasons that are nothing to do with the team."
Asked to explain Ferrari's lack of pace, he first brought up the row over the new F1 aerodynamic rules, which some teams interpreted differently from the traditional leading runners.
The Brawn, Toyota and Williams teams exploited a loophole in the regulations governing diffusers, the influential part of the floor of the car between the rear wheels.
The row was settled in F1's Court of Appeal between the second and third races, and now all the teams are racing to implement their own version of the 'double-decker' diffuser.
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Montezemolo said: "We have seen very badly written rules. They are what I call grey rules, with different interpretations.
"And if teams that have won the last three world championships, like Renault, McLaren and Ferrari, and important team and car manufacturers like BMW and even Red Bull, have one interpretation, it means that at least the rules are not clear.
So, very unclear rules means different interpretations, which means different cars in the field."
Ferrari's boss also revealed his frustration at the introduction of Kers this season.
"It represents a lot of money. It represents something that has been introduced to have a link between F1 and advanced research for road cars in terms of energy, and in terms of green [technology] and in terms of innovation.
"We have done the Kers immediately, even if it means a lot of money, safety, and reliability and it means to project a completely different car - as McLaren have done and as a lot of other teams have done.
"But we have been surprised to see Kers was just a suggestion, not a [requirement]. And today we are facing a very strange and in my opinion not positive situation.
"We have three different F1 on the grid - we have F1 competition cars with Kers, F1 competition between cars with no Kers and a different floor, and third competitors with no Kers and no floor.
"This is bad, and it is one of the reasons why unfortunately we are not competitive and we are forced to invest time, and extra money in such a difficult moment, to do a heavy modification to our car.
Montezemolo admitted that in trying to win the 2008 F1 crown when Lewis Hamilton pipped Felipe Massa to the title at the Brazilian GP, Ferrari was unable to devote time to developing a car for the 2009 season.
"Another reason is that we have started to work in a hard way to the new car late," said Montezemolo.
"And this was a pity, particularly in a year in which the rules have been completely new. It is not, in other words, an evolution of last year's car, and this is a second reason why we have not been competitive.
"And the last reason is that I feel inside the team there has been a little bit too much of a presumptuous approach.
"Sometimes to put the head down in the ground is useful to looking ahead, but I must say that sometimes having your whole head, feet, everything in the ground, even more underground, is better."
Ahead of the China GP, Ferrari revamped their pit team, handing team manager Luca Baldisserri's track duties to engineer Chris Dyer.