Success in Formula 1 is all about mastering variables: optimising the performance of the driver, the thousands of the components that make up an F1 car, and the black rounds of rubber at each corner.
But one of the most taxing variables for the teams this year is one they have no control over whatsoever: temperature.
Some of the effects rising and falling temperatures have on the cars are predictable. For example, hotter conditions require larger vents to cool both machine and man.
But it’s how changes in temperature affect how each car uses its tyres that has teams puzzled this year. It’s always been significant, but its importance seems to have increased. And the margins involved are slimmer: a few degrees up or down affects different cars in different ways.
It was a big story in Canada, where the weekend got progressively hotter, so that, in the race, the competitive order was jolted. Lotus and Sauber came through in the final laps to claim podium places at the expense of Ferrari and Red Bull.
Valencia was supposed to offer teams a weekend of reliably hot weather from which they could get a better handle on their performance. But so far it hasn’t quite worked out that way. Cloud cover on Friday pushed the track temperature down from the usual high-40C range into the 30s. Consequently, those teams who headed the times on Friday may be unsure whether they will stay there when the blazing sunshine returns.
Vettel aims for third victory
Sebastian Vettel has scored back-to-back wins here in the last two seasons and was quickest of all on Friday.
Red Bull have brought in another upgrade for the RB8 – in the shape of revised exhausts – and some aerodynamic tweaks. It remains to be seen if they will race them but they appear to have found some improvement.
No driver has been able to win two races so far this year but Vettel is a good candidate to change that this weekend. He’s had pole position twice already this year and is priced at 2.00 to do so again here.
Force India are dark horses
Which team had its drivers in the highest positions at the end of practice? It wasn’t Red Bull, McLaren, Ferrari or any of the usual suspects: it was Force India.
The Silverstone-based team had a disappointing run in Canada with both cars finishing out of the points. But they appear to have unlocked some of the VJM05’s potential and improved their understanding of how it performs in higher temperatures.
Here is a team that’s definitely worth keeping an eye on; it remains to be seen whether they can replicate their performance in Saturday’s final practice session in conditions which are expected to be hotter.
Pay particular attention to Paul di Resta, who’s qualified well this year and is particularly strong on street courses such as this. He’s currently priced long at 40.00 for pole position and the same to win.
Look out for Lotus
Before the weekend began I tipped Lotus as one of the teams to look out for. Past results suggest Romain Grosjean and Kimi Raikkonen have one of the most competitive cars in hotter weather.
The pair were eighth and eleventh in second practice, with rookie Grosjean once again leading 2007 world champion Raikkonen - though one shouldn’t necessarily read too much into that in practice.
That difference is reflected in slightly shorter odds for Grosjean to take pole position: 16.00 compared to 20.00 for Raikkonen.
Keith Collantine is the editor of Formula One blog F1 Fanatic.