Statistics show that winter traffic accidents account for 40% of the overall accident rate in recent years, and some people say that you should not drive a rear-drive high-horsepower sports car in winter. Pirelli and Ferrari have come together to answer all this. 
What are winter tires?
Pirelli engineers told us that many people are Xi referring to winter tires as snow tires, which is inaccurate.
According to international standards, tires used in environments under 7 are called winter tires, and the kind of snow tires with nails seen in rallies are special tires with nails and very narrow widths, which are considered special accessories and cannot be used on social roads.
Today we are talking about winter tires that are practical for ordinary snow. Winter tires may be a very foreign thing to drivers in the South;But for friends in the north, this is a must-have magic weapon for winter driving.
The role of the tyre is to provide grip to the vehicle, and all the characteristics of the vehicle ultimately need to be translated into dynamic driving performance through the engagement of the tyre with the ground.
The grip of a tire is not only related to acceleration and braking in the longitudinal direction, but also to the steering in the lateral direction. It is not only related to the output of the engine, but also determines the efficiency of electronic auxiliary systems such as ABS and ESC.
Compared with ordinary tires, winter tires are specially designed for low-temperature ice and snow roads, and winter tires can improve grip on low-temperature adhesion roads by "soft power".
In addition, the friction on ice and snow roads is improved by reducing the gap between the pattern blocks and increasing the number of rubber blocks, so as to help the vehicle maintain stability and control when driving on snowy roads.
7 degree standard
So when is the best time to switch to winter tires?
Pirelli engineers told us that the correct number was 7. How do you arrive at such an accurate number?There are pictures to speak:
At around 7, winter and summer tires have a similar elasticity. As the temperature decreases, the grip of the summer tires will drop sharply, and the elasticity of the winter tires will increase as the temperature decreases.
7. How much is the difference between summer tires and winter tires?
On wet roads, the braking distance of winter tires is up to 10% shorter than that of summer tires. This 10% is almost the distance of a car body, and it is also the distance that can save a car accident.
On the ice and snow roads in the north, someone has done a set of tests, and the final result is: under 40-0km h braking, the braking distance of summer tires is 13 meters farther than that of winter tires. The body of the general family car is about 4 meters, that is, it can have 3 more bodies!
Therefore, many countries in the European Union stipulate that the time point for replacing winter tires is also subject to low temperature below 7. Of course, in some countries in Europe, there are countries that stipulate that winter tires must be used within a fixed date range.
Winter tires have their own unique characteristics compared to regular tires, one of which is that winter tires do not harden in low temperatures.
Whereas, regular tires stiffen at low temperatures, affecting grip and handling. Therefore, in low temperature environments, the use of winter tires can effectively improve grip and reduce driving risks.
When the Ferrari Portofino M meets Pirelli winter tyres
We all know the theoretical knowledge, so what does the winter tire feel like in actual driving?
For this Ferrari and Pirelli winter tyre tour, I deliberately chose a Portofino M that I had not had the opportunity to test drive before, and drove 1,000 kilometers for two days without changing hands.
The final conclusion is that Ferrari's GT is really good for long drives, provided you get four Pirelli winter tyres in temperatures below 7 degrees.
After the "high temperature" of 20 degrees in Shanghai in winter, the cold wave suddenly hit, and the temperature in Shandong suddenly dropped to about 2 degrees.
Before the Roma, the Portofino was the Ferrari with the lowest barrier to entry. The positioning is similar to that of the Roma, and it is a two-door, four-seater GT sports car.
But in terms of appearance, I personally think that Portofino is more Ferrari, while Roma is considered "the Ferrari that is least Ferrari".
In terms of body size, the Portofino is average among GT sports cars, with a length of less than 4.6 meters, a width of about 1.94 meters, and a height of more than 1.3 meters. It's a little smaller than the ROMA, not to mention the Martin DB11 and Bentley Continental GT.
The rear of the car is relatively short and the design is relatively simple. Ferrari's classic twin round taillights with a high-mounted brake light in the middle. Although it is an entry-level model, the exhaust is still four, and the momentum cannot be lost.
Honeycomb mesh vents around and above the exhaust pipes, with a diffuser at the bottom. Compared to the old Portofino, the Portofino M has no exhaust muffler. Thanks to the use of an adjustable exhaust valve, the exhaust back pressure is reduced and the sound is improved, and the weight of the exhaust system is reduced.
The interior design is still familiar with the "Ferrari taste", with turbo-shaped air conditioning vents, a carbon fibre multifunction steering wheel with LED shift lights (this is an option, which integrates driving modes, suspension lift, push-button start, lights, wipers, paddle shifters and other driving-related functions), R, Auto, Launch buttons on the centre console and, of course, Ferrari's signature yellow tachometer.
The power part is still the familiar F154 series engine, 39-liter V8 twin-turbo. Codenamed F154 BH on the Portofino M, it has a maximum horsepower of 620 hp and a maximum torque of 760 Nm, an 8-speed wet dual-clutch gearbox + front-rear-wheel drive, which is the same as the Roma.
Ferrari models are fitted with CCC-certified winter tyres, which ensure safe driving and better control of the road when temperatures are below 7 degrees Celsius. Dedicated tyres and original wheels help the Prancing Horse to its full performance, both on the road and on the track.
Developed for winter performance, the Pirelli Winter SottoZero delivers performance with cutting-edge technology that strikes the perfect balance between comfort and performance, never slacking off during the coldest season of the year, delivering outstanding performance and significantly reducing driving risks in harsh winter conditions.
The high-performance winter tyres presented by Pirelli at this event, the Winter Sottozero Serie II, designed for high-horsepower models, are popular with high-end car manufacturers such as Ferrari and are the protagonist of this winter review, and are installed in the Ferrari test drive.
Its tread has an asymmetrical tread pattern and is divided into two distinct parts. The inside side provides effective drainage, and the outer side is more rigid and the tread blocks are more spaced to provide good grip on snowy surfaces.
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