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Interlagos marked the second consecutive pole for Cadillac, factory team partner JOTA, and Alex Lynn, behind the wheel of the gold #12 machine.
It was a magnificent lap, exactly a tenth faster than his teammate Sebastien Bourdais, in the #38 car, and over quarter of a second faster than Julien Andlauer in the #5 Porsche.
Cadillac have been on pole once before this year, at Le Mans. While it was a magnificent lap from Alex Lynn on both occasions, in France and Brazil, at Le Mans the polesitting #12 Cadillac, in the hands of Will Stevens, was passed on the first lap by Andlauer.
From then on Cadillac didn't have the pace of the front runners, although they still finished fourth and sixth.
Cadillac and JOTA's aim will be, obviously, to prevent a repeat happening in Interlagos.
But how?
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Cadillac focusing on preserving tyre life
As Lynn told us at Le Mans, the Cadillac V-Series.R is good over a lap due to a pointy front end, or at least a car that's less prone to understeer, and therefore theoretically faster, than its rivals in qualifying.
James Jackson
But in the race, this philosophy choice causes undue tyre wear due to excessive sliding from the rear end. This, combined with Cadillac's lack of top-end straight line speed at Le Mans – by just a few kilometres per hour, but it matters – put paid to their chances of a win last month.
So, it's something the team have been focusing on in Brazil.
'I think honestly, the thing with our car is making sure we can do 6 hours with good race pace,' said Lynn after qualifying.
'We know we can do one lap really good, but it’s about making the tyres last and making sure we make the right strategy calls.
'Basically, make sure the tyres don’t degrade more than the others, and I think honestly that that’s the main thing we’ve been focusing on and the main thing we need to improve to make steps forward as a team.'
Interlagos is known for the stress it puts on tyres, with the long, fast, banked final putting energy and therefore heat into the rubber. The lap then also features a slow speed second sector, which being relatively slow, doesn't allow tyres to cool down.
The track was resurfaced last year, but the surface is still quite abrasive. This helps the cars with mechanical grip, but also causes higher tyre wear than a smoother surface would.
Bourdais has 'difficult weekend' before quali
On the other side of the Cadillac garage, Sebastien Bourdais had struggled a little in the #38 car before qualifying.
'Up until Hyperpole, we just had a really difficult weekend,' said the veteran Frenchman.
'It's just been a succession of little miscues that gave us a couple of wrong reads and I felt like it just kind of threw us a bit down the rabbit hole.
'A few more tweaks to the setup and it was OK in FP3. So, you go in qualifying, and you have no real idea of what the car is. Plus, traffic was an absolute mess in that first bout of qualifying.
'Thankfully, we made it to Hyperpole and now you have a better idea of where the car is at, what it’s doing. It just it worked a lot better for me.
'I still made a mistake and didn't really get that best lap, but you’re always kicking yourself a bit. Very happy for the team. Congrats to Alex and we’ll see what we can do tomorrow.'
Unfortunately for Bourdais, he lost second to Andlauer for impeding Peugeot's Paul di Resta in the initial qualifying session, dropping the #38 Cadillac to third. The #5 Porsche, then, will start on the front row alongside the pole-sitting #12 Cadillac.
Top speed vs second sector pace
Looking at the sector times, Bourdais was two hundredths up on Lynn in the first sector. He then lost 0.065 in the second sector, putting the deficit to Lynn at 0.045. He then lost a further 0.055 in the third sector, to take the final deficit to Lynn up to exactly a tenth.
This first sector from Bourdais, a 21.179, was the fastest of anyone through the session, 0.019 up on Sheldon van der Linde in the #20 BMW.
Lynn was then fastest in the second sector, setting a 41.983, with Bourdais second. Lynn's second fastest lap was third quickest in sector 2, with the closest non-Cadillac belonging to Porsche's Andlauer.
The Frenchman was, though, 0.151 slower than Lynn's best in that sector. So, clearly the Cadillac is working well in the slow speed corners, where understeer can badly kill your lap time as it delays how fast you can get back on the throttle.
Peugeot's Malthe Jakobsen was quickest in the third sector, which stretches from just before turn 12, the slow left hander, then onto the banked straight towards the finish line.
The Dane was over a tenth and a half quicker in that sector than Lynn.
To add to that, Cadillac's strength at Interlagos certainly isn't ultimate straight line speed. That crown belongs to Porsche.
The speed trap sensor is on the main straight, just before turn 1. In Hyperpole, the fastest speed was recorded by Porsche's Kevin Estre, in the #6 car, at 294.8kph. Cadillac's best was 288.6kph, from Sebastien Bourdais.
We learnt from Le Mans that the Cadillac, maybe, generates a little more drag than the Porsche. This was why Cadillac complained about the car's 'raceability' – they were struggling to overtake, because while they were generating similar lap times, they didn't have the ultimate straight line speed required to make overtakes.
It could be a similar story here at Interlagos, then. But, Interlagos has significantly more twists and turns than Le Mans over its 4.3km lap. If the Porsche is set up for straight line speed and the Cadillac is set up for being fast in the twistier sections requiring more downforce... it promotes an interesting battle between two very different cars.
Whatever happens, it promises to be an interesting battle at Interlagos.
Feature image: DPPI / WEC
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