Darth-Piekus wrote: ↑02 Nov 2024, 20:59
Watto wrote: ↑02 Nov 2024, 20:53
Just see it as RBR playing mind games that are part if F1 for years. Ignore it
McLaren with the bib stuff I think is nothing and this is just a return of serve nothing to see here.
Unless there is more actual proof. Then I tend to let it go as mind games of F1.
It reminds me of Ferrari back in 2003 when they forced a rule change to the tyres as Michelin has done a better job than Bridgestone and Kimi was leading the championship with a last years Mclaren.
Hi Patrick, you here on F1technical? Or is it you Ron?
Jokes aside, and sorry, but I have to make it clear that Ferrari did not force a change in the rules back then. To say this is simply wrong and you need to know something of the origins and historical facts of said rule (which Ron and Patrick knew full well, because they were actually involved in it and the discussions around it and disqualifications and measurements after every pit stop and race!).
The rules were very clear and stated that the tire could have a maximum size of 355mm, with a maximum tread width of 270mm. Literally "BEFORE the race" was written in the regulations but this was due to the simple fact that when these tire rules were introduced in 1998, not enough was known about the behavior of the grooved tires and F1 and the FIA wanted to avoid disqualifications for tires that were too worn and that they would have been forced to measure every tire after the race. You might need to know this historical fact to avoid being hoodwinked by the public relations and press of the time by Michelin, Williams and McLaren, who had to somehow justify their and Michelin's...."trick". Some call it a trick, others call it a letter of the law, others call it cheating. Everyone can judge that for themselves, but ultimately it was nothing more than a deliberate breach of a rule that the FIA in cooperation with the teams had deliberately drafted in a vague manner years earlier to avoid unnecessary complications and inconsistencies and against the intention of this rule.
The reasons why Michelin did what they did were manifold:
In 2001 Ferrari had already understood the advantages of an appointment of weights able to provide greater load on the front axle to provide greater load on the front axle to produce a better developed capability of inserting the car into a corner. With an output of 900 hp, a torque of 40 kg/m and circumferential forces of more than 1,000 kg/m in the contact area between the road surface and tires when accelerating from 100 km/h, there is no longer any question of mechanical traction. Ross and Rory understood very early that it was much better to rely on the electronic traction control systems until, at around 180 km/h, the aerodynamic load and the drop in thrust generated by the higher gear ratios stop the wheels spinning and transfer the load to the front wheels. In this way, the deceleration capacity was favored, so that the braking effect at the entrance to a corner and increase the speed of yaw. However, due to the difference in responsiveness and the technological advantage Ferrari had over Williams and McLaren, it was Michelin and not Bridgestone that turned this new kind of balance into a design parameter. The result was a front tire that ignored contradictions of an aerodynamic nature and favored the acquisition of the largest possible contact patch. In reality, Michelin went one step further and adopted a linking profile between the carcass and the tread connection profile that acted as a real hinge under braking, as the load increased due to the weight transfer to the front axle, increasing the contact patch beyond the level prescribed by the regulations, making them almost 1mm bigger than the maximum allowed. Thus, in the first phase of the season, a contradictory situation was found in which those who had the greater load on the front axle did not have tires capable of taking full advantage of it, while the competition, which did not have the load, achieved the same effect due to the characteristics of their tires. Ferrari knew about the function of the Michelin tires from the Monaco Grand Prix onwards and after threatening to protest during practice in Monza, the French company relented. If you looked at the contact patch of the tire in a static situation, you were able to see an approximately rectangular surface with more or less rounded edges and the elementary transverse and longitudinal forces of the contact (surface pressure) are distributed symmetrically to the axles. This situation changed when a longitudinal force was applied to the contact surface as a tensile and braking torque. The shape of the contact surface and the distribution of the pressure are subject to strong fluctuations. The longitudinal expansion decreases with a significant narrowing of the circumferential surfaces of the pressure parallelepiped. This is a consequence of the fluctuations in the stiffness of the boundary caused by rolling, responsible for the movement from the center
in the direction of the deforming lateral force of the following contact. When a lateral force occurs under these circumstances (e.g. when entering a corner), a deformation of the tread is detected, forcing the tire to move no longer in the direction of its average plane, but at a certain angle with respect to the ideal trajectory. Much of a tire's efficiency depends on controlling this slip angle. The battle for supremacy between Bridgestone and Michelin had been determined in large part by research into the maximum amount and progressiveness of change in the resultant forces acting on the contact patch, with the aim of achieving predictable and reliable performance on which the driver's perception of the limit of adhesion directly depended. This was a very complex objective when dealing with a Formula 1 characterized by vertical forces that were extremely variable in relation to speed, as well as exceptional longitudinal and lateral loads. There were of course a lot of "mechanical" instruments with which to intervene in the footprint. Like today - with the height of the vehicle above the ground, inclination of the wings, you
could influence the vertical load. The position of the center of gravity as well as the suspension and damping properties of the suspension system determined the dynamic load transfer. However, it was obvious that the best result was achieved by optimizing the above parameters, both with regard to the specific characteristics of the tire used and vice versa. If one
starting from a formula identified with the tires, nothing else is done but to synthesize a real solution in which the car and tire designers work as a perfectly integrated team, in which all the mechanical and aerodynamic solutions interact with the characteristics of the tires, creating an interdependence that excludes that the simple replacement of one tire with another on a competitor's car proves to be more effective and turns into a car advantage. In most cases, the characteristics of the dynamic deformability of the tires cannot be "compensated" by simply adjusting the pressure and angular characteristics, cornering, caster and toe-in. It became well know later that Michelin's technicians, together with those of Renaut, had developed a form of front suspension whose operation had been subjected to the characteristics of the tire, with a unique mechanical system capable of restoring the natural positive camber that occured on the inside of the wheel in a bend and which limited grip. This is one of the unknown secrets of Renaults sucess in 2005&2006,
in addition to the well-known mass damper, gearbox and the special weight distribution and they deliberately took the opposite path to Ferrari, whose advantages they believed they could not make up for with the same approach. Anyway - the "three-element marriage" between the type of compound, the structure of the carcass and the characteristics of the vehicle was therefore indissoluble and defined the area in which tire manufacturers had to work. In 2003, Michelin achieved outstanding results, in particular by deepening the phenomenon of "grip under slip", which
assumed the name adhesion force. This was/is a transitional phase in which the adhesion limit mixes with the lower adhesion limit, characterized by a particularly high level of adhesion but countered by a marked instability of adhesion values. Michelin sought to improve the predictability of handling in the real "grip limit", where the driver was constantly active, and worked on the structure of the carcass using composite materials with boron fibers, on the number and expansion of these fibers and on the impregnation of the carcass. The structure of the tire was also differentiated between the sidewalls and the tread in order to absorb the variations in stiffness due to the constant changes in the ratio between longitudinal and lateral forces. Michelin had focused its attention in particular on a unique adaptation of the carcass to the bead, differentiating between the inside and outside of the tire in order to obtain a response with specific stiffness, capable of choosing a different response to vertical and lateral loads. It was precisely in this area of technology that Michelin's peculiarities lied compared to Bridgestone. As today, camber was one of the tools available to the technicians to adapt the functioning of the tire on a Formula 1 car.
A large negative camber on the front wheels increases the grip of the tires without causing uniform temperature variations. When cornering, with the development of roll, which is contained by the stiffness of the suspension but still always present, the camber tends to cancel itself out (camber recovery) so that the tire is exactly perpendicular to the road at the apex
of a corner, a condition in which the contact patch is as large as possible to counteract the considerable lateral forces that occur in this phase. It should be noted that negative camber causes an asymmetric contact patch whose area increases from the inner edge of the tire to the outside, creating a lateral force that is canceled out on the straight by the interaction of the wheels on the front axle, but becomes a centrifugal force when entering the curve, when the drive of the inner wheel decreases. The Ferraris on Bridgestone tires had adopted this theory, with camber angles between 5 and 10 degrees, depending on the track. But increased camber also brought with it remarkable contradictions. When braking, for example, the contraction of the front suspension due to the load transfer caused by the deceleration of 4 g or more caused a further increase in the angle of the front wheels in relation to the road surface, leading to a corresponding reduction in the contact patch at the very moment when maximum grip is required. In addition, increased static camber contributed to the wheel coming out of play on the inside of the bend and being condemned to take on positive values that reduced its effectiveness. A consequence that could have been neglected in a slow curve, but which was crucial in a fast curve, when the aerodynamic load that limited load transfer amplified the function. Michelin took a different approach and gave the tire itself the task of ensuring a negative camber value regardless of the suspension geometry. With this strategy, Williams opted for the double keel, which increased the volume of air to create the ground effect, but restricted the length of the wishbones and compromised camber recovery in the corner. If we look at a car equipped with Michelin tires today, especially the Renaults, its easy to see they had camber values close to zero. As already mentioned, the asymmetry of the contact patch from which the lateral force emanated was due to a particular type of tire construction, which had a differentiated structure with a stiffer inner shoulder and a softer outer shoulder.
But long story short - in the end, Michelin designed a tire whose tread area exceeded the 270mm allowed during the race and grew like a hinge to 278mm due to the construction. The fact that "before the race" was written into the rules in 1998 due to the not 100% predictable characteristics of the grooved tires does not change the fact that the rules were broken here. In such cases, I think you always have to look at extremes, which makes it easier to really see whether it was against the rules or not. Would it have been ok if the tread had not increased by 0.8mm but by 50cm during the race? I don't think anyone can answer "yes" here with the best will in the world, and in the end it doesn't matter whether it's 0.8mm or 50cm. It is still often used as an argument that Ferrari had already known about these tires since Monaco (in fact, it was already suspected something like this beforehand, but that's another story), but said nothing. One has to be aware of one fact - in F1 you play your cards strategically and tactically. You have to do that if you want to be successful. That's why you will never reveal an opponent's infringements of the rules if you have them under control. You only play this card when it is necessary and when he becomes a danger. Or if he suddenly gets the better of you, which brings me to McLaren and Red Bull.
The Pirelli tires have a very narrow temperature window of 5 degrees Celsius, which is really very small. A small amount of water on the inside at the right time, as a spray mist directly onto the interior surface
can help a lot without making any real trouble regarding tire pressure. I don't know the composition of Pirelli tires, of course, but the molecules of any water vapor produced (remember that the pressure inside the tire is between 1.4 and 1.8 bar, which means that the boiling point of the water increases to 127 degrees Celsius) should be able to penetrate the tire wall, so it should have little effect on the tire pressure. However, as the boiling point is between 127 and 130 degrees Celsius anyway due to the pressure, little to no water vapor should be produced (with 110-115 degrees Celsius being the optimal temperature for all the Pirelli tire compounds, if memory serves)And a small amount of liquid that slowly dries and escapes is unlikely to have a negative effect. It would therefore be an absolutely effective method of keeping the extremely temperature-sensitive Pirelli tires within the ideal window and avoiding overheating and degradation. However, a valve inside the tire would be about as difficult for the FIA to find as a fingerprint-covered knife in the back of a murder victim. Not to mention the associated lines to the valve... So if McLaren has not installed self-dissolving lines and valves, this is probably a baseless accusation. Theoretically, this would probably even be possible, because there are materials that would dissolve accordingly or through additives, but their particles would still be detectable. And the usability in an F1 car is then rather impossible and this sounds more like a conspiracy theory than reality.
With regard to the aforementioned argument of the unsprung mass, I would like to say that given the importance and sensitivity of the tires, a few grams of weight can be given preference to unsprung mass. Because in the end, a few grams more of unsprung mass in favor of better functioning tires make up more lap time than a few grams less of unsprung mass with overheating tires. Ferrari, for example, added 2000 grams of unsprung mass, the F1-2000 to the F2001 compared. This is a lot, but it improved the stiffness of the suspension (mainly camber stiffness and toe stiffness, not so much vertical stiffness) to such an extent that the durability of the tires was so much better that it outweighed the disadvantage of 2000 grams of unsprung mass by a lot. And here we talk about approximately 50 gramms of water or another fluid. This amount would be negligible in every respect with regard to the advantage in terms of tires and even if it were water and evaporated, it would have virtually no significant influence on the tire pressure.
