Lewis Hamilton’s data confirms clear theory on W15 upgrade package

Pablo Hidalgo
Lewis Hamilton and George Russell fighting for position

Lewis Hamilton ran Mercedes' new package while George Russell was on the old spec in Mexico

Lewis Hamilton edged out George Russell in the Mexican GP race after a tight but fair battle between the two Mercedes drivers.

Hamilton raced again this weekend with the W15 upgrades while Russell raced with the old spec, allowing the team to assess the impact of the Silver Arrows’ latest big package for the 2024 season directly.

How Mercedes ended up with different spec cars

George Russell suffered an accident in qualifying at the last US GP where he damaged the new W15 parts he had fitted. Mercedes had to send the upgrades back to the Brackley factory for repairing them and had only one other spare set to fit. The team decided to save it for the Mexican GP.

Lewis Hamilton decided to use these spare upgrades despite the poor performance they gave him at the US GP, while Russell has been running the old spec all weekend.

What the latest Mercedes W15 data shows

Qualifying and race data showed a big difference between the two W15 specs which ultimately resulted in an advantage for Hamilton to overtake his teammate in the race.

This difference was also due to a very different set-up choice between the two cars. But Mercedes at least confirmed the theory they have been carrying since Austin: the car with the new upgrades must be set up with less downforce to get the full potential out of it.

At a circuit like Mexico where, due to low air pressure, cars tend to run with larger wings to compensate for the lack of downforce generated, Hamilton ran with the lowest downforce wing of all, giving him a visible advantage on the long straight, but compromising his performance in qualifying, especially in Sector 2 and Sector 3 in direct comparison with Russell.

Mercedes upgrade - Hamilton v Russell

Mercedes upgrade - Hamilton v Russell

In terms of race performance, this visibly lower downforce set-up compared to Russell meant that Hamilton struggled a lot in the first stint with his medium tyre management. After overtaking Russell at the start with better speed, Hamilton was overtaken again on lap 15 and thereafter the gap between the two increased linearly as the laps went by.

Mercedes upgrade - Hamilton v Russell

Hamilton pitted on lap 28 when he was +6.1s behind Russell. The seven time World Champion quickly began to push hard on the new set of hard tyres to try and close the gap to his teammate who was still on track with old tyres.

Russell pitted three laps later and Hamilton’s undercut had a big effect as the gap was reduced to just +2.7s. Hamilton’s pace on fresh tyres and in clean air, despite having to overtake Franco Colapinto, was astonishing.

Mercedes upgrade - Hamilton v Russell

Russell then encountered traffic as Liam Lawson and Oscar Piastri were still on track extending their first stint. The Mercedes driver had to attack and lost time and tyres unnecessarily. Hamilton also encountered them further ahead, but had an easier time overtaking them.

By lap 35, again the two Mercedes cars were in a direct fighting position with freedom to fight against each other as the team let Russell know over the radio on lap 50 when Hamilton got to the back of George’s car to start his attacks.

After 15 laps of hand to hand fighting with no contact and a lot of respect between these two great drivers, Hamilton managed to ‘catch’ Russell on lap 66 on the outside of turn 1. Looking at the telemetry, we can clearly see the impact of the DRS effect and the lower downforce of Hamilton’s car to finally complete the overtake.

Mercedes upgrade - Hamilton v Russell

After suffering in the first stint, the difference in performance with less fuel under race conditions was clearly in favour of the car with the upgrades fitted. Mercedes seem to have found a much better set-up route than in Austin with a complete different approach this time.

Nonetheless, they still have to find a better compromise between top speed and downforce level. And despite this upgrade package, the worst news is that Mercedes are obviously still a way behind Ferrari, McLaren and Red Bull.

Mercedes upgrade - Hamilton v Russell

Russell is expected to fit the upgrades again for this week’s Brazilian GP. Hamilton, if there are no surprises, will also continue with the upgrades as he has already done this weekend.

Hamilton remains in P6 in the Drivers’ Championship with just 12 points separating him from Russell. Despite having lost the head-to-head qualifying battle this season with a clear 5-15 in Russell’s favour, Hamilton is being more consistent on Sundays and, with four rounds to go before the end of the season, he has the upper hand over his teammate before he changes to Ferrari.

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