The Indian Grand Prix from a tire point of view

Oct. 22, 2012

Formula One comes to India for only the second time this weekend, and just like last year Pirelli will bring the P Zero Silver hard and P Zero Yellow soft tyres. However, these compounds are softer compared to their equivalents last year, and with a better knowledge of the Buddh circuit plus some real data, Pirelli can afford to be less conservative this time – which should lead to even closer racing.

Compared to the last grand prix in Korea, where Pirelli brought its two softest compounds, India places heavy demands on the tyres. This is due to a number of factors, starting off with the high ambient temperatures in excess of 30 degrees centigrade. The track layout also takes in several fast corners that put plenty of lateral energy through the tyres: in particular the banked turn 10, which is similar to the famous turn 8 in Turkey. The front-left tyre is subjected to an acceleration of 4g on the exit of the corner, where maximum grip is required to hold the racing line, but the tyres are actually under full lateral load for six seconds during the corner, which increases wear.

At the beginning of the lap in particular, there are some notable elevation changes that exert vertical forces on the tyres as well, combined with a braking force of 3.6g into turn 4. The main straight, which is more than a kilometre long, is one of the longest of the year: while tyre tread temperature peaks at over 100 degrees centigrade during the course of the lap, it tends to cool down considerably by the end of the straight.

As the circuit is not used extensively during the course of the year, a high degree of track evolution is expected over the weekend. A dirty track causes excessive wheelspin as the cars struggle for grip: this also increases tyre wear. Generally though, the surface of the Buddh circuit is quite smooth, which means that degradation is contained.

Pirelli’s motorsport director says:

Paul Hembery: “There was an amazing atmosphere and an extremely warm welcome at the Indian Grand Prix for us last year, so we’re all looking forward to going back. This year we know a little more about the track so we’ve made a less conservative choice, with the hard and the soft tyres striking exactly the right balance between performance and durability. The circuit layout is one of the toughest that our tyres will face throughout the second half of the season and it’s also the last time that we will see the hard and soft combination this year, which was previously used in Barcelona, Britain and Japan – which gives you some idea about the demands of this circuit. The Buddh circuit has been specifically designed to encourage overtaking, which is also one of the objectives behind the design philosophy of our tyres, so we should be set for an action-packed race at a crucial point in the championship.”

The men behind the steering wheel say:

Narain Karthikeyan (HRT): “Last year the tyre choice was understandably a bit conservative, but with all compounds slightly softer for 2012 and the track in fantastic shape, it may be a different story this time. The layout is a great mix, which makes it challenging for the tyres as there are very few conventional corners, barring turn 1 and maybe the final corner. The first gear exit at turn 3 punishes the rears if you are impatient with the throttle. At turns 5-6 you are turning and scrubbing off a lot of speed simultaneously so it’s easy to test the limits of the track at the exit. There are a couple of fifth gear direction changes as well, with the esses of turns 8-9 and 13-14 negotiated at well over 200kph. Finally there’s the seemingly unending turn 10, where you have steering lock on for over six seconds while the minimum corner speed is just under 200kph, putting tremendous energy into the front-left. So overall, it’s a fairly busy lap but since the surface isn’t abrasive, wear shouldn’t be issue. We’ll have to wait until the Friday sessions to find out what we can expect in long runs with both compounds. The goal would be to see how the softs perform on high fuel. Obviously this is the most anticipated race on the calendar for me, there is already a great buzz around the event considering that the championship is still wide open and I hope all drivers and F1 personnel relish the Indian experience.” 

Pirelli’s test driver says:

Jaime Alguersuari: “I think that the layout of the Buddh circuit is one of the best in Formula One, and it also happens to be one of the toughest on the tyres. I’ve got good memories of the track personally too: last year I finished eighth after a good qualifying as well. You get this interesting combination of low, medium and high speed corners, as well as long straights. A lot of the corners are quite unusual: for example we have a chicane right at the end of the lap that we take in fifth gear, which doesn’t happen very often! What puts the biggest stress on the tyres in India is the fact that many of the corners are very long, so there is a sustained lateral load with some fast changes of direction as well. You need all the grip you can get and there is a risk of graining as well if you do not manage the tyres properly. The hard and the soft tyres are a very good choice here – the hard will be perfect to race on – and I think that a one-stop strategy could be possible if you look after the tyres in the correct way.”

Technical tyre notes:

  • There was a performance gap of up to two seconds per lap between the two nominated compounds last year, but this year the gap should be a lot smaller, allowing the majority of the front-runners to get through Q1 on the hard tyre.
  • The asphalt of the Buddh international circuit was brand new last year, but one year on the characteristics of the surface may have evolved. A new circuit gradually releases oils from within the asphalt, which forms a slippery layer on the track surface. Over time however this film gradually disappears, giving it more grip and making it more abrasive.
  • The pit lane in India is one of the longest in Formula One at around 600 metres. This leads to a relatively significant time loss when changing tyres, which is an important factor when considering the race strategy.