Paul Hembery has revealed that Pirelli have adopted a "worst-case scenario" for next season as they have very little data about the cars.
Although Pirelli will continue to supply the teams with tyres for next season, the many changes that F1 is set to undergo means the tyre manufacturer has very little to go on.
Without knowing exactly what demands the cars will put on the rubber, Hembery says his company has adopted a more "conservative" approach.
"We've done a survey of the teams and how they envision the cars looking and it is very clear that the development speed of the teams will be very fast," the motorsport director told the official F1 website.
"But, of course, at this stage the teams will not give us any more information because this is a competitive environment and I am sure they don't want to be compromised.
"So we have taken worst-case scenarios based on the data that we have and we are working towards that. Having that in mind, we have to be a little bit more conservative."
Pressed as to what a "worst-case scenario" was, he insisted that "was just a phrase!
"What I meant was related to top speed, lateral loads, vertical loads, aero loads, the loadings on the front and the rear. You have to create a car bringing together all the data from all of the teams - a car that doesn't exist, that is a fictitious car, but which is the worst-case scenario in terms of the parameters we're looking at.
"Of course with the huge changes in regulations the teams will, step-by-step, learn to understand what they really mean and we'll need the data very early on to understand where they are. We'll then keep asking to be updated during the season.
"In pre-season nobody will give too much information - as I said, this is too competitive an environment - but once we are running we need to be very clear on where the journey's going as we don't want to repeat the errors of this season."