Barcelona Test 2: Why were 2013 cars 1.5 seconds faster than their 2012 counterparts?

Mercedes F1 W04: The car that has surprised everyone with its pace

One of the very interesting things that came out of the 3rd pre-season test at the Circuit de Catalunya was the fast times with which Mercedes and Ferrari blistered the timesheets, especially during the last two days of testing. On the penultimate day, 2nd March, Lewis Hamilton surprised everybody by comfortably dipping below 1:21. His fastest time was a 1:20.558 which was set during a low-fuel, 5 lap run, 1 hour before lunch. That time really caught everybody’s eye, specifically because Hamilton himself last year, in a McLaren no less, had set a pole laptime of 1:21.707 (although it did not result in him starting 1st on the grid) at this track.

At first sight it would definitely surprise anybody that a Mercedes is lapping a full second faster than a McLaren – that too in less than optimal conditions – which in turn was on an average 1-2 seconds faster than the Mercedes last year. But there is more here than meets the eye, as is explained later on. That becomes more clear when some teams like Lotus and Ferrari didn’t seem too impressed with that laptime, saying their cars too can achieve those times with ease. Even then, we should take into account the fact that the Mercedes W04 is a much-improved car and is looking like it can compete at the very sharp end with Red Bull, Ferrari, McLaren and Lotus.

Day 4 of the second Barcelona test proved that it was no flash in the pan for Mercedes when Nico Rosberg went even faster to lap the track in Montmelo in 1 minute 20.130 seconds (this was done on a 1-lap run). To prove to Mercedes that they are not the only ones capable of setting such times, Ferrari sent their double world champion out on a low-fuel run and Fernando Alonso managed a 1:20.494.

So what is it that is making this year’s cars significantly faster than last year’s? There has been not much change in the technical regulations to result in such a significant difference in pace. Then, what is the mystery behind it?

The mysterious Pirellis: the big headache for the teams

One answer: PIRELLI. The most important change from 2012 to 2013 has been the Pirelli tyres. The Italian tyre manufacturer has changed the construction of the tyres to provide more traction out of the corners. Also, they have softened the sidewalls but strengthened the shoulders. Not only that, when one compares this year’s tyres to those of last year, every tyre type (Hard, Medium, Soft, Supersoft) has been made softer so that they provide more grip and hence better laptimes- the 2013 Hard being similar to the 2012 Medium and so on.

This explains why W04 was so much faster than the MP4-27. The Spanish Grand Prix, at Catalunya, was held early last year when all the teams were having problems keeping their tyres in the correct working ranges. It was proving to be difficult to bring a brand new set of tyres to their optimum working conditions for that all important final Q3 flying lap.

As a result of all this, this year’s tyres heat up a lot faster and hence are much easier to bring up to their individual working ranges. So, even if the conditions are not perfect – track temperature and ambient temperature – the tyres can still perform at their peaks very quickly. But these tyres have a downside as well. Having become softer, their life has been reduced. As we saw during the two tests in Barcelona, all the teams were suffering from serious tyre degradation due to graining. The “graining” we are talking about here happens during to very low track temperatures -there is not enough grip and hence the tyre ‘peels off’.

This kind of graining is not expected in Melbourne in two weeks time where it will be much hotter. But with the tyres having significantly changed, they remain the biggest unknown factor, as accepted by Ferrari Technical Director Pat Fry. During the Friday Melbourne practice sessions, time would definitely be devoted to learning more about the tyres and how they operate in track temperatures around 40^oC, some 25-30 degrees higher than what the teams experienced during the winter. On an average, it is expected that every race will see 1 stop more for each car, compared to 2012.