The crucible Why goodyear goes racing
The • cruclb 1 Why Goodyear goes racing
If Formula One is an iceberg, in all its various aspects, then 99.9 percent of the development that goes into tyres is firmly hidden beneath the often far from tranquil surface. Back in the middle of 1992 the FIA (at that time still the FISA1 decreed that tyre widths must be reduced for the following season, and introduced new legislation to that effect at a stroke. To the layman, the idea of taking three inches off tyre width might not seem such a big deal, but to men such as Perry Bell, Goodyear’s Chief Engineer, Race Tyre Programme, it meant cramming more than six months’ work into two as he and his team at Akron set not only about designing new tyres, but also making sure that they were as efficient and effective as the predecessors.
“Overall, that’s a 16 percent reduction, so it’s more significant than you might think. We started designing in July of 1992. One of the goals was to avoid air freight shipping charges, because all of the tyres were being built in the US and would then be shipped to Europe. That meant the tyre design process had to be complete and the tyres released to production by February. The problem is that we have to consider our other race tyre production commitments in the US. That was all part of the incentive to complete the job quickly. It was a very accelerated process.
“You’re also faced with the fact that initially you don’t have access to race cars designed to the new regulations. We went to Estoril following the Grand Prix in 1992. That was our first evaluation of the new tyres. But we were still testing with modified cars, and that did lead us astray a little. If anything the cars became better balanced, and easier on tyres, as the season progressed. The initial tyre tests indicated that the cars would be required to race a compound one step harder than that used in 1992 at the majority of the circuits. However, after the first couple of races it became apparent that we were able to use compounds very similar to what we used in 1992. Maybe half a step harder. “In designing the new tyres we were
trying to take into consideration what was happening at the front of the vehicle as well as the rear, striving to keep the car relatively well balanced. We were trying to compensate for the loss in front aerodynamic downforce, because of the front wing changes, by narrowing the front tyres. his, we reasoned, would allow the race car designers to regain front downforce to balance the vehicle. However, when we arrived in Estoril for our first test, everyone looked a the tyre package and said, ‘Oh, wow, the fronts are way too big!’ Now, if anything, the teams want the front tyre a little bit bigger. You’re always fighting that! The teams have their own impression of what they think they need. We all work together to satisfy the needs of each customer. However, sometimes we have to remind these customers that the tyre is a complicated structure and that our record over the years demonstrates our understanding of the fundamentals of tyre design and compounding.”
Part of the problem that faced Goodyear with the narrower tyres was that the regulations still insisted on the same diameter, so there could not be a commensurate increase in tyre wall to cater for the reduction in width.
“That was the major problem with the rear tyre. The maximum 0/D had to stay at 26 inches. The FIA was not interested in changing that. We were negotiating for a better compromise, but they insisted on standing firm with the regulation the way it was originally written. That was part of the delay in getting started. We needed to be certain of the tyre dimensions before we could order the moulds to produce the tyres.”
Moulds, of course, are one of the biggest expenditures and most timesensitive factors in any new tyre programme, particularly with wet tyres. “That was the next problem. The dry moulds, we were able to produce relatively quickly, but the wet moulds required longer lead time. We actually went with an interim rain package. It was definitely a compromise, but it was the best we could do. With the new rear tyre
we went to the Aquatro tread pattern, but at the front we had to go with a modified Gatorback pattern for the first two races.”
They got some rain in Brazil, but thf new Aquatro tread fronts were ready by Donington, which would prove distinctly good timing!
“It was a very exciting programme. Probably one of the fastest race tyre programmes that we’ve ever done. And it all worked out very well. I was very pleased with the way it all came together. Personally, 1 think it went so smoothly that people just took it for granted!” He laughs. “I felt that perhaps even our management didn’t appreciate the magnitude of what was done. For us it was really some undertaking, and we had no margin for error. We had to rely on simulation data as well as the data the Fl teams were supplying us. This information provided us with the speeds and expected tyre loadings that needed to be taken into consideration in designing the overall tyre package. We really just had one, possibly two shots at it.” Multiply any problems by the number of cars running the tyres at a race meeting, and you begin to appreciate the potential magnitude of the problem if anything did go wrong. . .
“We had to complete the testing and give the race tyre recommendations to production as soon as possible, because the first race was in South Africa, which is quite a ways to get to, and then on to Brazil. We had to have production for the first three or four races completed before the start of the season to put us in position for the remainder of the year. What people don’t realise is that the races where production really starts to become tight is when you get your Magny-Cours, Silverstone and Hockenheim. Production requirements for those races just start building and you have to have your act together. You have a big lead time at the beginning of the season and it looks like you will not have any problems producing the required quantity of tyres. But by mid-season the races start coming back-to-back, it’s like being on a slide.” With the width and diameters fixed, Bell and his team preferred not to stiffen the sidewall, but rather to concentrate on the cavity shape. “We modified the shape to produce a tyre which would meet the new reduced width regulation But we had to increase the tyre air pressure because there is a direct relationship between contained air volume and the load a tyre can carry. The air pressure inside the tyre had to be Increased to compensate for the reduced volume because of the narrower tyre width. We had to push very hard with
the teams, because they were used to running only 16psi at the rear with the wide tyres, and we were telling them they had to go up to 19psi. They were shaking their heads, ‘Oh, we can’t do that!’ But they worked with us, they understood where we were coming from. So we were able to compensate for the 16 percent reduction in tyre width by modifying the mould cavity shape and increasing the air pressure. “The FIA not only reduced the width of the tyres, but in the interest of reducing the cost of racing to the competitors they also put a limitation of only seven sets per race meeting. So once again that didn’t give us any margin for error in determining the proper tyre recommendation. if we had to do anything we would err on the conservative side, because we certainly didn’t want to get ourselves into the situation where the recommendation was too soft and the tyres were blistering, because then seven sets might prove insufficient for the entire meeting.
In fact, nobody had any serious tyre problems in 1993, and the only public failure was Damon Hill’s when he was leading the German GP at Hockenheim. “That was an unfortunate incident,” says Bell quickly, “but the evidence indicates that the tyre lost air because of a Puncture. The data acquisition showed that the tyre did not lose air suddenly, but the air loss occurred over a short period of time which is consistent with a typical puncture. We were never able to totally confirm this. The tread and belt package were never returned because of supporting races immediately after the GP. For this reason we were not able to examine the tread surface for possible cuts or punctures. That was an unfortunate incident, and I hate to see that.” As Bell is well aware, without opposition the only time there is a real tyre story at a race is when something goes wrong . . . It’s a testament to what Goodyear achieved in such a short time for 1993 that people barely noticed there had been a tyre regulation change. But nevertheless, Bell would welcome some opposition. “Everyone says, ‘We’ve got this monopoly at the races, isn’t it great?’ Well, from an engineering standpoint, no! It’s not very rewarding. Race against yourself, and you race only to not have a problem. You have a tendency to be somewhat conservative. When you’re racing against competition, you feel, from an engineering standpoint, more satisfied. You know: ‘Our tyre is a better product.— Part of that was disguised, however, by the teams’ use of traction control to promote better grip out of corners and to save the rear tyres. but Bell has some
interesting observations on that subject that tend to be borne out by the lack of drama there has been since traction control was banned. Some observers predicted a spate of tyre problems now that there was nothing to protect the narrower rears, but it hasn’t worked out that way.
“Traction control certainly clouded the issue, and still the question in my mind is: ‘What was the end result of traction control? Did it help us or did it hurt us?’ “Obviously now 1 think it helped. But with treadwear, I think if anything it probably in many cases increased tread
wear at the rear. Without traction control, the driver could feel the tyres spin and he would back off to save them. With traction control you were able to optimise the setting to generate a certain level of slip all the time. The driver just put his foot in it and drove away, so you were always getting a certain amount of slip. You’re not breaking it away, but you’re probably getting continually, over the life of the race or pit stop, a higher level of slip than the driver would be able to control himself.” Even without traction control, Goodyear is still looking within the same compound range for its 1994 tyres. Spain was potentially tricky, with the FIA limiting downforce but being a step out with limiting power, but that was recti
fled by Canada and in any case nothing untoward was evident in Barcelona. Again, that’s a tribute to the work that went into the new tyres.
Motor racing is a perfect proving ground for Goodyear, not simply because it places its products in a crucible, but because its personnel and techniques are formed there too. “We like to think of it as a training ground,” admits Bell. “What our engi neers learn in racing, they can apply in other areas of the company. They learn to think on their feet, many times making proper decisions with only limited amounts of data. And they have the opportunity to evaluate and receive
rapid feedback on many new concepts. And once these engineers move from racing into other areas of the company, they also have the ties back to racing, and they talk back and forth. A good example of this is our new dual-channel Eagle Aquatread: the engineer that designed that tyre did in fact come from Formula One. We talked with him quite a bit as we were developing the Aquatro Formula One race tyre. The end result was the Eagle Aquatread. We designed the Aquatro in 1992, and the Eagle Aquatread passenger tyre was introduced to the marketplace in ’94. That’s typical of the time required to take a passenger tyre design from concept to the marketplace. Obviously, to develop and design a race tyre the requirements are a lot different than developing an 80,000-mile tyre. While we have model
ling techniques and accelerated tests to evaluate long term performance it still takes time to verify 80,000 capability. “That’s what gives racing the ability to evaluate so many different things so
quickly and get instant feedback. In a really competitive situation, we can be reacting in two, three, four weeks, quickly developing new ideas, evaluating these ideas, and getting results. “We like to think that racing provides the perfect environment to develop new engineers. They experience the full tyre development spectrum in racing. The engineer develops the concept, designs the tyre that will utilise the concept, writes the specification, follows the tyre through the factory in the production facility located in the Technical Centre,
and then goes to the racetrack and sees the application of his concept first hand. So he gets the full gambit, all the way from designing the tyre, following it through production, going into the field
and performing the sales engineer role. It certainly gives the engineer a better appreciation of what he’s doing, especially in a competitive situation.” And it gives you better road tyres, too. DAVID TREMAYNE