Brought to you by TJ13 Courtroom Reporter & Crime Analyst: James Parker

First of all, I would like to welcome you all to episode two on our journey that explores turbo charging in Formula 1. In the first episode, we looked at the drivers from the distinctive era in question, in particular at who is best suited to the new regulations in 2014, and who got it right during the fearsome 80’s.

So, onward to episode two then. Today I will shift my focus to the fabled subject of tyres: how did they differ during the 1980s and what can we expect in 2014 with brand new regulations. I understand that you, dear reader, are probably crying out in pain over yet another article regarding Formula 1 rubber, but bear with me on this one.

The key questions
Tyres, these pesky little blighters, splits opinions in Formula 1 in 2013 more than ever. They are the root of all evil to some and the bringer of light to others. So, what about the fabled turbo era then: did the turbo cars spark any differences in the construction of Formula 1 tyres? What can we possibly expect to happen in 2014, when the characteristics of the entire car change to those similar of the eighties?

Rubber in the eighties
The characteristics of the turbo engine cars were vicious, outputting vast torque figures that would light up rear tyres in fifth and even sixth gear.

“The car was like a bomb at circuits like Spa, Austria and Monza. And the power was unbelievable – even if the turbo delay was terrible. You’d open the throttle at the entry to the corner only to get the power at the exit. And if you missed it by five or 10 metres, there was nothing you could do – you just spun it. The lag was about one or two seconds. At Zeltweg, down the long straight to the Bosch Kurve, the car was throwing out 1400 bhp and just kept on pushing – you felt like you were sitting on a rocket.” – Gerhard Berger speaking about the Benetton BMW B186

When you have drivers speaking that way it is easy to see why the cars of that generation are considered the scariest of all time. These were the “monsters” that pushed tyre development to its limit and the era saw numerous changes made to the rubber used in Formula 1.

At the very beginning of Formula 1’s turbo era, Michelin was pioneering a new radial tyre, over the bias ply structure that was being used by the majority of the grid. This new, radial design offered numerous benefits.

The standard and acknowledged bias ply tyre of the time consisted of multiple rubber plies overlapping each other. The crown and sidewalls were effectively interdependent. These overlapping plies formed a thick rubber layer that was prone to a minimal amount of flexing and was quite sensitive to overheating.

Michelin highlighted these flaws and sought to rectify them by introducing the radial tyre, which allowed the sidewall and the tread to function as two independent features of the tyre, thus minimising heat sensitivity and increasing tyre flexibility. This increased flexibility therefore maximised the contact patch of the tyre yielding greater overall grip, which allowed for a faster lap time. The benefits were huge.

With the incredible torque that the turbo engines delivered (approaching 1000 bhp in qualifying trim by 1983), the car’s rear traction and management of overheating were key to producing a predictable and solid race tyre for the drivers.

It was not until 1984 that Michelin’s main competitors – Goodyear and Pirelli – started to introduce their own radial-construction slick tyres. By that time, Michelin had won the 1983 Formula 1 season with Brabham, and was set to dominate again with McLaren, which they did. After 1984 however, Michelin had lost the initiative with regard to the tyre race and pulled out ahead of the 1985 season, leaving Pirelli and Goodyear to duke it out.

With power reaching upwards of 1400 bhp at full boost and in qualifying trim , the turbocharged Formula 1 cars presented big headaches to both Goodyear and Pirelli. Qualifying tyres were commonplace for teams, which led to spectacularly quick qualifying laps. At the time, Pirelli was renowned for producing “super-sticky” qualifying tyres, which yielded incredible grip over 1 lap.

When bolted on to formidable qualifying cars such as the Brabham and Benetton, which also had the BMW M12 engine, they led to quite dramatic results. The Pirellis could also be “reconditioned” by scrubbing them down so that they could do more than a single run on a set of tyres.

Goodyear, however, held a trump card with their race tyres. Much like today’s hard, soft, and medium compounds, both Pirelli and Goodyear produced numerous race tyres, codenamed A, B, C, D, with A being the softest, used on very high speed circuits like Monza, whilst D was the hardest compound, used on demanding circuits like Imola.

But whilst Pirelli’s softest compound was brilliant, since it was built following the same principles as its qualifying compound, they could not match the C and D compounds in terms of durability and performance. Goodyear on the other hand, by exploiting these characteristics, started to monopolise the grid, with the likes of Williams and McLaren as customers. This meant they dominated Formula 1 from Pirelli’s demise in 1986, when Goodyear was named sole tyre supplier, up to the end of turbo-charging in Formula 1 in 1988.

So, what of 2014 then?
As we know, during the 1980s the construction of Formula 1 compounds was radicalised by Michelin in order to deal with the demands placed on them by the excess torque of the turbo power plants, with radial tyres becoming the norm in the Formula 1 paddock as cars got faster and faster.

For 2014, we still don’t know who will be the tyre supplier in Formula 1. With Pirelli not having signed an agreement (cue possible fallout from the Mercedes tyre test) and Bridgestone making it clear they are not interested to come back to Formula 1 could we see Michelin back in Formula 1?

What we do know, however, is that the engines will be much more vicious than their naturally aspirated counterparts. The tyres not only have to deal with the turbo torque but also the application of almost 160hp. Heat management will be the biggest headache for “the tyre manufacturer” to deal with as traction issues will be ever more prevalent, with low-down torque increasing tenfold off corner exit.

Like in the eighties, the construction of the tyres may have to be radically overhauled in order to comply with these new characteristics. Obviously, this season the carcass of the tyre has been reinforced with a steel belt rather than a Kevlar one, in order to stop the internal blistering seen in 2012. The idea is to keep more of the tread in contact with the tarmac. This, however, has meant that the tyres have suffered from increased heating problems due to the increased stress.

The above has led to the changes Pirelli made to produce a new compound for the rear tyres, to be introduced for Silverstone. Hence, in that regard I am fascinated to see how the construction of the compounds varies once more next season.

Taking this into account it appears overheating will be the teams’ sole worry in 2014. The centrifugal forces and loads that the tyres will be subjected to in 2014, with the increased slip angles at the rear, will mean that heat management will be key for drivers keeping their tyres alive.

Conclusion
During the eighties, the new demands presented by the ludicrous power being put out by the turbo cars led to tyre manufacturers having to completely redesign the structure of the tyre compound. In essence, the tyres were just as influential in differentiation of the cars’ performance as they are today.

The manufacturer who, in the past, best combined the demands of qualifying performance and race performance essentially reaped the rewards of success. This just so happened to be Goodyear.

In 2014, heat management will be influential in determining the durability of the compounds – a lot like in the eighties, when heat management issues triggered a change to radial tyres by ALL manufacturers. In 2014, the turbo engine’s characteristics are possibly the most radical in the sport since the last time we flirted with turbo charging technology and, therefore, now technology has increased tenfold, the same principles apply.

Cars will be rear-limited in terms of grip to an extent that we have never seen beforehand with naturally aspirated engine regulations and it therefore presents a brand-new challenge to drivers and engineers. We have heard Paul Hembery state in the phone conference last week that drivers could expect wheel spin in third and fourth gear so, therefore, thermal degradation could potentially be the biggest problem facing teams in terms of tyre wear in 2014.

In the final episode, I will explore the differences in the cars themselves and how the ones taking to the track in 2014 will vary from those who raced during the 1980s. Stay tuned for part three.