Korea Analysis: Individual Race Battles

Posted on October 25, 2011


As the analysis done at intelligentF1 normalises out the effects of the safety car, it is quite easy to extend this to producing the race from the point of view of one car. Therefore, some of the battles which played out at the Korean Grand Prix can be viewed from the point of view of the driver by a simple extension of the intelligentF1 tools which manipulate the data. The intelligentF1 model itself will not be plotted in this analysis, but it can still help understand what is going on. These are not unlike the battle charts on f1 data junkie.

The two battles we will look at are the Rosberg/Alguersuari battle for seventh, and first, the Buemi/Di Resta/Sutil battle for 9th-11th. The chart below is normalised to Sutil’s race (orange line), with Di Resta represented by the orange crosses and Buemi the pink line.

Buemi’s pace can be seen as stronger than the Force Indias right from the start of the race, even though he had to pass the Williams cars before catching Sutil. Di Resta gained initially, but then was slightly slower on the option tyres in comparison with Sutil on the primes. Both Di Resta and Buemi stopped before the safety car, and Sutil stopped when it came out on lap 17. He thus had fresher tyres, and passed Di Resta in the second stint. Buemi could not pass Di Resta on track, but his pace increases when Di Resta pits. The upwards gradient on Di Resta’s curves after his pitstop shows the undercut effect very nicely. Suddenly, he is going faster than Sutil, and comes out quite clearly ahead after his stop. Buemi’s pace is more remarkable – he stops the lap after Sutil, and still comes out ahead. Buemi’s pace can finally be seen clearly after the second stops relative to the Force India cars and he takes a comfortable ninth. It is also this stint in which Di Resta beats Sutil – as Sutil’s tyres are four laps younger, he should be catching Di Resta at about 0.4s per lap according to the intelligentF1 model. As the gap is maintained, Di Resta’s pace is stronger in reality, and this gets him the final point.

Now let’s consider Rosberg and Alguersuari. In the chart below, the race is normalised to the point of view of the Toro Rosso (pink line) and the grey line is the Mercedes.

Rosberg is clearly quicker in the first stint on the option tyres, but this pace advantage is never seen again. After the safety car period (laps 17-21), There is little to choose in pace between the cars – Rosberg’s tyres are a few laps older suggesting that he has a pace advantage. In fact, the intelligentF1 model suggests that this makes precisely the same pace advantage as seen in the first stint. It is, however, the next part of the race which is key. Rosberg damaged his tyres defending from the Ferraris and made his final pitstop very early (lap 28). Instead of pulling away on new tyres as would be expected, his pace is essentially matched to Alguersuari’s. This is due to Alguersuari going faster now Rosberg is out of the way, and Rosberg being much slower than his pace from the previous stints in real terms (according to the intelligentF1 model). This appears to be fuel and tyre saving, and tactically it seems to pay off when the team judge it correctly and Alguersuari and comes out behind the Mercedes after pitting. It cannot be seen on this chart, but Rosberg then accelerates the pace, but this is not enough to shake off Alguersuari. The Spaniard had tyres which were 10 laps (a full second) younger and the intelligentF1 model suggests he is faster on the prime tyres in real terms in addition. The Mercedes was therefore very vulnerable, and only Rosberg’s straightline speed advantage could save him. It nearly did.