Didier Perrin: the new F2, “an evolution more than a revolution”

How was the car designed?

Before starting, we first checked that we could modify the current car to adapt the 18-inch rims without completely calling into question the suspension system, braking, etc., because we wanted to make the transition with reasonable costs.

Beyond the tires, what has been changed on the car?

There have been minor changes to the suspension: the hub carriers sit higher compared to the rest of the car. We also made aero changes, since the increase in the size and mass of the wheels increased the frontal surface area of ​​the car and hence the drag. There is now more space between the discs and the rim. And all of this, obviously, was not going in the right direction for the performance. We therefore installed panels to close the inside of the rims, so as to prevent the air flow from passing through the wheels and disrupting the functioning of the rest of the car's aerodynamics. Generally speaking, it is an evolution more than a revolution.

How do you explain that, despite the increase in weight and drag, the car seemed faster than last year in Bahrain?

To compensate for the negative effects of drag and weight, flat bottom extensions were added to give more efficiency to the diffuser, while increasing engine power a little to obtain 25 to 27 additional horsepower compared to to last year. Finally, we had the happy surprise to note an increase in performance which is due to the additional gain obtained by the tires by Pirelli.

Pirelli didn't have much time to design the 18-inch F2. Does this worry you?

No. I have no concerns about their ability to develop their tires. They already have experience with 18 inches. Remember, we did tests in Monaco in 2015. Pirelli has been working on this for a long time, and this kind of diameter is used frequently in other disciplines. Pirelli did not start from a blank sheet. I never had the slightest worry. This winter, it was more the brakes that worried me…

That's to say ?

The car, in its 18-inch configuration, will go faster than in 13-inch. So as it is faster and heavier, if we stick to the laws of physics, the brakes will be used more. Despite everything, we did not question the diameter of the discs because that would have meant changing too many components on the car. This is why we have chosen to pay particular attention to cooling the discs and calipers with new scoops adapted to the new shape of the rims, because we know that the brakes will have more work to do.