Bridgestone Motorsport UK Technical Manager Hisao Suganuma explains to Timothy Collings why recent discussions in the media about the use of mixed compound tyres, front and rear, are not only riddled with inaccurate theories and potentially illegal practices, but also propose ideas that would reduce a car's performance and competitiveness on the track instead of delivering any improvements...
Mixed compounds: against the rules, against bridgestone philosophy and against all common sense
"We have never used mixed compounds, front and rear, and we always respect Formula One's rules and regulations," said Hisao Suganuma, Bridgestone Motorsport UK Technical Manager, stressing that, as we all know, for a Japanese owned and world respected organisation, it would be inconceivable to consider taking any 'short cuts' that led to even a remote possibility of improved performances.
"We never have done and we have no intention of ever doing anything in the future that is contrary to the regulations." Those who know Bridgestone and understand the Japanese will not have any argument with this.
"We always respect the rules and regulations and, if we are not allowed to do something, we would never do it," he added. "So, that is our principle in this job and it is our only way in attempting to achieve our objectives. That said, it is worth explaining also, to many people who do not understand, that there is no performance gain, in my opinion, to be made from some of the ideas that have been discussed recently."
Speaking at Magny-Cours, where the Formula One circus arrived last week in preparation for the French Grand Prix, Suganuma said it was difficult to explain precisely why some cars' performances varied, or appeared to vary, from one day to the next. However, he stated, that is not cause for any misleading suspicion.
Citing the example of Ferrari's perceived loss of performance at Monte Carlo, he said: "To be honest, it is very difficult to explain why Ferrari's performance was notably better on Thursday, in Monte Carlo, than it was on Saturday. We have tried to find out why it happened and sometimes you have to say that there are other points of view to consider.
For example, if you look at it from the other way around, you might ask: did we lose performance -- or did they (our direct rivals) gain in performance through the weekend?
"For example, did the conditions change during that weekend and become more suitable for our rivals' tyres? These days, now that Formula One is in a competitive situation so far as the tyres are concerned, the performance is always relative to our main rivals and, from that point of view, it is difficult to know if we lose, or if they gain, in performance.
"The gap can still be the same. So, for example, if I try to explain how this kind of thing happened, I might suggest the following (and this is only my supposition).
"As an example, say our rivals brought softer compounds than us to a place like Monte Carlo. Firstly, the Thursday track conditions are quite 'green' and, in other words, more abrasive. So, that would mean that, with softer compounds, it would be easier to get graining on the front, which develops understeer. That is why our rivals' cars may not get the good lap times then - because they have too much understeer.
"On the other hand, the Bridgestone tyre is harder than that of our rivals in Monaco. That means it would perform well on Thursday because less graining means less understeer. Furthermore, the car balance in Formula One is very important and, if the Bridgestone car had good balance, that may help to deliver better lap times, relatively speaking, than later in the weekend when the track has more rubber laid down."
Invited to delve into the hypothetical notion, as suggested in some quarters, that a narrower tyre, using a different, harder, compound, at the front would produce a significant aerodynamic and, therefore, performance advantage, Suganuma was amused and surprised.
His long experience in the business of designing and managing a supply of racing tyres had taught him this was likely to produce exactly the opposite effect: that is to say it would produce a performance disadvantage.
He said: "I don't think there is any performance advantage to be gained in following the suggestions made, to have narrower and harder tyres at the front. It is said that a narrower tyre will have better aerodynamic efficiency, but if you remember what Bridgestone did, when grooved tyres were introduced, in 1998, you will understand. Then, we made a wider and bigger tyre for McLaren.
"We were told by the McLaren aerodynamicists that, from their computer simulations, we would lose half a second, or something like that. But actually our car, with McLaren, in that year, was quicker. The performance was better with that combination and our rivals followed that example from mid-season."
Suganuma also recalled that he spent a long period in charge of Bridgestone's involvement with the Japanese Group C sportscar championship in the early 1990's. In that series, tyre suppliers were permitted to use different compounds for the front and rear and he discovered that it was more effective to run with softer tyres at the front than at the rear.
"It is clear that to go with a harder compound at the front would not be correct. So, if the regulations allowed it, I would do softer compounds at the front and harder at the rear because the rear tyre has to cope with nearly 900 horsepower - and that is a huge amount for that size.
"So, we always face high degradation at the rear, towards the end of a race and, from that point, if we had a softer tyre on the rear, relatively speaking, then the car would have too much understeer, initially, and then too much oversteer...it would never be balanced. So, that would be wrong."