Among the Macau Grand Prix race categories, three major races, F3 Grand Prix, Guia Race (World Touring Car Championship round) and GT Asia, rely on the control tires that are exclusively supplied by Yokohama Tire. On top of this, the competitors of the other supporting races, where they have freedom of choice for their tires, often choose the Japanese manufacturer's product in their quest for the victories.

Especially, Macau F3 Grand Prix which began in 1983 has had only one official tire supplier throughout its history to date and Yokohama Tire celebrated its 30th anniversary as the official supplier last year.

Besides the annual F3 race event in Macau, Yokohama Tire also serves extensively for other open wheel single seater categories and, in 2013, supplies the control tires for the Japanese F3 Championship, Formula 3 Cup Germany which is effectively the national F3 championship in the country and other junior formulae, such as Super-FJ in Japan or BRDC F4 in U.K. As for the Japanese F3 championship series, Yokohama Tire is contracted as the official supplier until the end of 2016.

But, in terms of public attention, Macau F3 Grand Prix is probably the biggest of all. Because the top contenders from the F3 championships around the world are gathered in Macau to race and the event is considered as one of the major stepping stones for the world class motor racing categories.
Here, we speak with Yuichi Kobayashi, an engineer from the development division of Yokohama Motorsport International and ask a few questions on the tire development work for the Macau F3 race.

To start with, let's check out the basic differences between the tires for the open wheel single seaters (formula cars) and those for the touring car based race cars. Recently, it is often said that the high end tin-top cars, such as the Super GT cars in Japan, behave almost like the formula cars. But the true purpose built formula cars are still much lighter in weight than the touring cars and very responsive in terms of handling. So, how different is the tire development work for the formula cars from the same task for the touring cars, responding to the differences in those cars' characteristics?

"Firstly, when you compare the formula cars and the touring cars, the basic configurations are different and the ratios between the stipulated tire size and the car's weight are different. So, naturally, many things are different in designing the tires for these two types of cars."

"The formula cars are very sensitive and responsive and that means, for example, if the dynamic balance of the tires aren't very good, the drivers are likely to experience the tire induced vibration. And we can use much softer compounds for the formula car tires. So, if a driver made a mistake of brake lock up, it can easily damage the rubber in that part of contact patch."

"Today, the F3 cars have a lot more aerodynamic load than they had before. But, in comparison with the touring cars, the F3 cars still weigh much lighter and their tires have larger air volume. This means the tire construction are rarely broken by external loads in the case of F3."

"In short, the tires for the formula cars are different in the compound range and the shape from those for the touring cars. Yokohama Tire has vast experience from a wide variety of motor sport activities from past to present, including the tire competition categories such as F3000 in Japan, and, of course, the knowledge is poured into the development work of the formula car tires in the present day."

Not limited to the Macau F3 race alone, Yokohama Tire has a long history as a single seater tire supplier, as Kobayashi said, and the company is now taking part in the traditional race meeting for the 31st time as the official tire supplier. But, first of all, how he thinks the control tires for Macau F3 Grand Prix should be like?

"Almost all drivers are visitors from other countries and they drive around the street track that provides very low grip level. This means the tires should be fairly forgiving to the drivers. Because the track surfaces, which normally used as public roads, has a low frictional coefficient, we choose relatively softer compounds."

"The drivers often struggle to warm up the tire properly in this race. This is partly because the cars are set up with only small amount of down force in order to go faster in the ocean side section. The cold front tires tend to slide too much and this causes the so-called graining wear. But this issue is now getting eased off by the recent changes in the tire design."

As mentioned above, the F3 cars are much lighter than the touring cars and, therefore, they are agile and very sensitive. The frictional coefficient of the street track in Macau is significantly lower than that of the permanent race tracks. These factors only boost the fierceness of racing between the promising young drivers from around the world.

By definition, the control tires in any category must be strictly equal to all the competitors. And those tires should be friendly to every driver and allow him or her to set the competitive lap time. On top of this, the tires must not be too fragile against punctures. So the control tires must fulfill the conflicting needs, which isn't always easy.

The control tires for Macau F3 Grand Prix have long been fulfilled those difficult requirements and earned the trust from the drivers and the race organizers. This is the reason why Yokohama Tire has continuously been the official supplier for the Grand Prix for more than 30 years. But what is the secret for providing the ideal control tires for Macau?

"The most important key is the continuity or, in other words, the fact that we have kept supplying the official tires for a long time. We have made gradual and continuous improvement over the long time period. For this year's race, we will introduce the new specification tires in order to improve the warm up characteristics, while maintaining the peak grip level and lap times that the last year's tires had."

"As I said before, it isn' t easy to warm up the tires and keep the temperature in Macau's street track. Plus, not a few drivers have accidents during the race and it sometimes leads to the Safety Car period. When the cars are running slow behind the Safety Car, the tires get cold but the drivers still need a good grip level at the restart. So, our main focus this year was to improve the warm up characteristics. I think making a lot of small improvements like this consistently is essential for the tire development work."

The race weekend of Macau Grand Prix is now closing in. This is the 60th edition of the Grand Prix and it spans two weeks to accommodate the increased number of races. The final race of the F3 Grand Prix is to be held on Sunday, November 18, and to conclude the whole race meeting. And this is the last question to Kobayashi. What does he feel on the eve of this year's Macau Grand Prix?

"First of all, I hope everything about the race goes safely without any problem in the tires. This is the 60th anniversary year of Macau Grand Prix but we would like to continue this partnership as the official tire supplier until when the race will celebrates its 100th anniversary! As for the categories other than the F3, we are aiming for winning all of the tire competition races."

This is the 31st year for Yokohama Tire to act as the official tire supplier of Macau F3 Grand Prix and the young lions from many countries will race each other using Yokohama Tire's product this year again. It is almost certain that some of those drivers will make their way to the top categories of professional motor racing, including Formula One.