I do think this interview engaging on a F1 italian site with Enrique Scalabroni could be very instructive. Here is the link:
http://www.newsf1.it/newsf1-speciale-in ... roni13193/
I tried with google translator with some minimum corrections and adjustments by myself. Hope it's understandable. Tbh, I think it is one of the most intelligent and instructive things I've been reading for a long time on this Formula One season. Enjoy.
Scalabroni interview
The name of engineer Enrique Scalabroni does not need any presentation for a Motorsport enthusiast: the long (and full of success) experience among Formula One (Williams "world champions" FW11 and FW11B, Ferrari 641 and 641/2 in the 90s with Prost, Lotus, Asiatech) and Endurance (with its "iridated" Peugeot 905 of the "invincible team" led by Jean Todt). Even throughout the aerodynamic development of Ford GT in the FIA GT championship... that make him one of the top expert engineers.
And we at
www.newsf1.it asked him some questions about the "hot topic" of the current Formula 1: the correct exploitation of the new "wide" Pirelli tires.
It is for me a special emotion to be able to interview the person who conceived and realized the car to whom are tied my first memories of "young passionate of Formula 1": the Ferrari 641/2 (with which the prancing horse achieved its one hundredth victory in F1), the only racing car to be displayied at MoMA in New York.
Engineer Scalabroni, however, puts me amiably at ease, and in this beautiful chat via Skype he answers various questions about the main issues of Formula 1 (and not only).
NewsF1- Eng. Scalabroni, thanking him for his utmost availability and kindness, I immediately come to this conclusion: Mercedes recently, by the mouth of his team principal Toto Wolff, complained to Pirelli not to receive "suitable" tires to his W08 ( implying, not even too much covertly, that the new "XL" tires are better suited to Ferrari. That accusation were readily forwarded to the sender by Pirelli CEO Tronchetti Provera).
But this is no longer due to an erroneous or defective job done in the pre-seasons tests by the Stuttgart / Brackley / Brixworth team?
Eng. Scalabroni- This year, with the rules changes introduced, it has led to cars that not only with the increased aerodynamic load but also with the newest tire that significantly increase the mechanical grip have greatly improved their speed in turns compared to the previous three years (+48 Km / h in some turns), it was necessary to start "almost" from a white sheet.
I say "almost" because Ferrari and Red Bull were able to take advantage of the background of two of their most prominent technicians, Rory Byrne and Adrian Newey, about the employment and maximum utilization of larger tires (background due to Scalabroni too, given his years of militancy in F.1 in the Goodyear period -n.d.r. ).
And these two teams designed cars with concepts that fully married these needs. First, adopting the concept created by Adrian Newey of "High Rake"
And with suspensive systems of quite "soft" calibration (the difference among Ferrari and Red Bull is currently chronically shrinking power from the Renault Power Unit, which does not allow the RBR car to develop with adequate aerodynamic load).
Softer suspensions and high rake trim, as well as allowing a [CX x A] "variable" product in relation to the speed, with the lowering of the rear in speed, decreases the drag (thanks to the reduction of the Cx [Coeff. Form] , due to the incidence of change, of a few degrees below the rear wing, resulting in the reduction of the master section [A] of the car), but then returning to standard values at lower speeds.
Additionally, suspensions with softer torsion bars make it possible to look for more mechanical grip by making the tire work in the right range of structural rigidity of the entire elastic assembly as well as in the right "thermal exploitation windows" that for these Pirelli tires can range from the 90 ° minima of the low-working range to hold to the 140th highest of the toughest high-working ranges (values, in absolute terms, quite high).
Instead, Mercedes followed a completely different philosophy, that's consequence of the one used in the three years previously dominated: a car with little rake, quite stiff from a suspensive point of view. Philosophy that does not seem to be the correct one for these tires.
In addition, the deep organizational change within the team goes hand in hand: Rosberg gone (who, for my direct experience, I can define a great tester capable of providing the correct technical feedback to the engineers), Paddy Lowe gone (equilibrium maker so far found) and inside James Allison. It is not a coincidence that Mercedes, with his arrival, has started to have problems similar to those that, until the end of last year, Ferrari had to get the tires in temperature.
Here, Ferrari was very good at understanding what was needed when drawing the 2017 car, as well as the "driving sensation" that was needed to provide the drivers, whose importance this year has increased considerably compared to the past.
And the Scuderia has been very busy in the tests, much more than the direct rivals (especially with Vettel, which also in the pace of race is really showing a state of grace), and the excellent demonstration is the performance of Raikkonen in Montecarlo qualifying, a clear example of a Ferrari that came to technical achievements (even in terms of development) so far.
Instead, Mercedes, with Hamilton and the "new driver" Bottas (recently in the team but still valid and fast), could take some time during the season before fully understanding how to use tires at better, due to the lack of participation, commitment and meticulousness, not to compare with to that one of Ferrari in Pirelli Testing during the 2017 tire development phase.
NewsF1- The "ban", also thanks to the letter from Ferrari Chief Engineer Simone Resta, regarding passive suspension systems tending to "simulate" hydraulically an active behavior, may have affected the current Mercedes performance defaillance?
Eng. Scalabroni - It could be, but not in such a high percentage as, on the contrary, deriving from the philosophical choices previously examined.
We can say that choosing the High Rake Car design allows us to find a better balance even with a shorter wheelbase (as in the case of Ferrari), while the longest wheelbase chosen by Mercedes, probably for a new distribution of the internal organs (engine , gearboxes) and aerodynamics (which, to reduce the Cx, must work at smaller ground distances, therefore with stiffer suspension suspension and less excursion) creates some weight problems and an increase in Polar Inertia Moment of the car in the act of changing the curve direction, resulting in a reduction in Angular Acceleration.
Consequently, we have a behavior that can create an understeering initial response (with the car that tends to "not turn") in slow and medium speed curves. In addition, the low rake trim requires the use of more rigid torsion bars to ensure that the rear axle does not go too close to the ground in order to not lose the efficiency of the rear diffuser. This excess of stiffness also generates lack of traction and overheating of the rear tires (due to wheelspin).
Consequently, an increase in the stiffness of the front suspension can give us a more responsive, reactive car, but even a car, due to modifyied set-ups to balance the rear end, that it's far more difficult to properly turn on the front tires, even during the braking phase. In addition to the fact, as noted in Monte Carlo, that it is not possible to pass over the curbs without excessive "slip".
NewsF1- The next GP, from a technical point of view, on the Canadian track in Montreal, what features will it require? How will be set the strength reports on the track between Mercedes and Ferrari?
Eng. Scalabroni- Certainly the long straight lines will make the Mercedes Power Units best able to express, especially in their most powerful mapping, but you also need to consider the asphalt quite disjointed and corrugated at certain points, in addition to the turns where you are looking for great skills of traction as well as some important braking phases.
And here might be important the least rigid setting due to Ferrari's High Rake.
In addition, a lower wear of the SF70-H tires (especially at the rear; Mercedes, on the other hand, seems to be more "problematic" in being able to fully discharge the power of the MGU-K generator, which, like every electric motor has a hight, flashy peak of torque) could be the key to a more correct pit strategy, which, as we saw in Monaco, could see "favored" the overercut. .