Friday practice is often unrepresentative of true pace; the cars are running different set-ups, energy deployment will vary, as will engine modes.
At Monza this weekend, one thing some teams will be trying to hide is their straight-line speed right up until qualifying, but we already had a fair idea of who might perform well.
With their Honda engine and ingenious chassis, Red Bull came into the weekend expected to be the fastest on the straights, just ahead of Ferrari.
Mercedes were more of a conundrum in that respect due to the draggy nature of their W13, so the question they needed answered was how much time they might end up losing to one or two of the midfield teams, such as Alpine for example.
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Further down the order, Aston Martin have been busy experimenting with different chassis and wing designs all year, and they arrived earlier this week with super skinny wings on the back of the cars driven by Sebastian Vettel, Lance Stroll, and Nyck de Vries – who contested FP1.
Williams, while being pound for pound the slowest on the grid this year, have a tremendously slippery car in a straight line, so they are ones to watch too.
Indeed, Nicholas Latifi was joint third fastest in the speed trap, measured just before the drivers get to the braking zone of Turn One, with Alex Albon and AlphaTauri’s Pierre Gasly level with him.
Sir Lewis Hamilton and George Russell were 12th and 18th, respectively, in a straight line during FP2, while Lando Norris and Daniel Ricciardo – both with Mercedes power in the McLaren – ended up in the top 10.
Alpine were not as quick as we might have come to expect as Esteban Ocon and Fernando Alonso both clocked speeds that were over 10kph slower than the fastest speed.
But it was Charles Leclerc in the Ferrari who went fastest on the straight with a speed of 349kph, 2kph quicker than championship leader Max Verstappen.
The difference in set-ups between team-mates was epitomised by the speed of Sergio Perez and Carlos Sainz, who both hit 340kph, putting them joint eighth with Daniel Ricciardo.
However, it cannot all be about removing every bit of downforce the car has and maxing out on the straight – this will not do.
The car has to feel confident on the brakes heading into the big stop zone of Turn One, and it needs to have the agility and the grip to make it through the Roggia Chicane, the Lesmos, and Ascari.
Even coming through the Alboreto corner at Turn 11, the exit is so important, as the following straight is the longest on the lap.
Launching off the corners onto the long periods of full-throttle is equally as important as having good straight-line speed so, if the car has the capacity for both, it is perfect for Monza.
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The significance of that quality showed itself in that Ferrari topped both of Friday’s sessions – first through Leclerc and then Sainz.
Mercedes and Alpine were both quicker than McLaren and AlphaTauri – to whom they had a deficit in the speed trap – in the opening session, but Norris crept up to fourth in FP2 with a great lap.
Ferrari initially took a one-two in the opening session, but Verstappen split them in the second hour, making for an exciting prospect heading into qualifying on Saturday.