PILOT SPORT CUP 2 FOR THE FERRARI V8 RECORDS
Exclusive tyres for top performance
The Michelin super-sport tyres make their market debut, selected as exclusive equipment of the sports car 458 Special Ferrari: halfway between slick and sports tyres, they show great consistency in tests at the Fiorano circuit.
Mino De Rigo
There is nothing better than a dynamic presentation on track for launching new tyres, particularly if at the top of the range. And if the car they are made for is the latest creation from Maranello, the sharp and super-technological Ferrari 458 sports car, and the circuit selected is Fiorano, in their own back yard. Certainly Michelin could not find a better context for the debut of the new Pilot Sport Cup 2. The new tyres are the only one approved for the car of the ‘prancing horse’ - a two years joint development. They are tyres of a new generation, able to move the performance pointer perhaps even higher than initially imagined. The 458 Special is the 8 cylinder with 605hp to put to test, able to accelerate from 0 to 100 km/h in 3 seconds. A car to engage on the track days, with the highest ever specific power (135 hp/litre), the highest lateral acceleration (1.33 g) and the quickest response to commands (0.06 seconds, in less than a blink); and even more, among the supercars of Maranello, it has also the primacy of the aerodynamic efficiency: 1.5 against the 0.98 of the Ferrari 430 Scuderia, racetrack version of the previous model. Thus explaining the need to go beyond expectations for the new Pilot Sport Cup 2. Says Olivier Bouhet, chief of Michelin tyres development: "these are tyres that are approved for road use, but their place is between the slick and sports (UHP), as a link between track and road".
In the road range of Michelin Man, the Pilot series Super Sport, is at the top level. "In May of 2012, when we launched the joint project for the 458 Special with the first analysis of the technical specifications of the car, the goals were immediately self-evident; to combine the top performance on the circuit with the pleasure of everyday driving. Then, with respect to the previous Pilot Sport Cup+, to improve the performances in both the wet and dry, delaying the onset of aquaplaning, and above all to increase the durability of the tyres, obtaining consistency of performance even after many laps". It may be surprising, given that this is in many ways an "extreme" tyre, but in the development phase, rolling resistance and noise have also been considered. We created a tyre with a EC label classification (a double E, instead, for the Pilot Sport Cup+) and external noise decreased from 75 to 71-73 db. The shoulder has been reinforced to withstand the wear and tear and was adopted a belt made of high density aramid fibre, so as to maintain constant the imprint of the new tyre, even at a higher speed. Among the further refinements, the bead is wider than the 10% compared to a traditional sports tyre, to the benefit of reactivity and precision in turns, and also the markings on the sides that, thanks to a micro-geometrical technique based on the contrast between lights and shadows, appear as on velvet. "We have taken into account” adds Bouhet “of all the different parameters and for this reason we have reviewed the product at the root. To reduce the sensitivity to aquaplaning we have chosen to increase the tread depth to 5.4 mm, against the 4.5 of the previous model. This has, however, forced to maximize the surface of the tyre with the ground", precisely because a deeper tread carving deforms more and therefore generates more heat, penalizing the performance. This explains the use of the innovative solution Track Variable Contact Patch 3.0, which optimizes the pressure exerted on the ground , in such a way that puts more tyre on the ground, to the benefit of grip. “In addition, to increase the consistency of performance on the circuit, we have worked on the distribution of the rubber compounds in the tread”. Which has a double compound, with a specific rigidity on the outside for the best adherence and grip, while inside is modulated for driving control, thanks to the initiating temperatures and the combination between elastomers and black carbon. At the base, the substantial technological transfer made by the Transalpine manufacturer from the tyres used in endurance racing. The manager of Michelin emphasises “the goal to raise high speed performances and at the same time taking curves at a reduced speed “. “With the previous generation of tyres” echoes Matthew Lanzavecchia, responsible for testing and development of Ferrari “it would not have been possible to bring the 458 Special onto the circuit and then safely back to open roads using the same tyres". The consistency of new tyres, tested on the circuit, has undoubtedly been very impressive even with typical winter temperatures (5 °C in the air and 1.5 °C on the asphalt on the day of testing at Fiorano). In the absence of comparative terms, we rely on tests done by Michelin in the Spanish circuit of Jerez. Compared to the Pilot Sport Cup+, the new tyres are by 50 % more enduring. Furthermore, from the graph that summarizes the performance comparison, it is seen as superior without exceptions. Handling and braking on dry surfaces improved by 9% and 7 % respectively, while the lap time is 3% faster. The result does not change substantially on the wet surface, with a 5% reduction in aquaplaning. "At the beginning of the project” says Lanzavecchia “we have worked very hard on the simulator, which has allowed us to monitor all the different parameters involved so as to obtain the highest integration. Once on the track, only fine adjustments were left". Contributing to the performance of the 458 Special, which employs solutions derived from F1, is a robust injection of state-of-the-art electronics. As the innovative system SSC ((Side slip angle control) which moment by moment calculates the car trim, using an algorithm that combines speed, steering angle and lateral acceleration. And then acts on electronic differential that makes it possible to recover stability or agility, depending on the situation. In fact, compared to the 430 Scuderia, the data of the ‘prancing horse’ record an 11% improvement in the steering wheel response, with a simultaneous 14% decrease of the steering angle. "We have spent a lot of time” concludes Bouhet “optimizing the car systems in all driving conditions. The results obtained proved us right".
SPECIAL 458, TRAINING LAB FOR THOSE WHO LOVE THE CIRCUITS
On one hand, the consistent and progressive performance of the Michelin Pilot Sport Cup 2 tyres, that equip the Ferrari 458 Special (245/35 ZR 20 91 Y size at the front and 305/30 ZR 20 103 Y at the rear), on the other a car system that exploits very intelligent electronic management.
Not only able to assist the driver in different conditions, but also to help him progress in the search for the limit thanks in particular to the match of SSC (Side slip angle control) and electronic differential.
The first recognizes when it allows the over steer without cutting the delivery from the engine, penalizing the performance, and the second acts in consequence.
A sort of training laboratory for wannabe racing drivers (the telemetry is among the car optional extras) that, with the shifter placed on "race", allows them to understand when they mistake. The system’s intervention with the improvement of the driving on track becomes less and less noticeable.