Sebastian Vettel took Ferrari’s first victory since the summer break in a tense and closely fought Brazilian Grand Prix. Having taken the lead from Valtteri Bottas with a fantastic start he held on to it in sublime fashion by perfectly countering everything Bottas did. Bottas was urged by his team multiple times to give it everything, but try as he might, he just couldn’t get close to even attempt a pass. It wasn’t a visually impressive fight by any means, but it was one of great mental strength. Neither driver, particularly Vettel, could afford to make a single error as doing so could cost them not only a chance at victory, but even the podium with Kimi Räikkönen following closely behind in P3, and Hamilton, who started from the pitlane, eventually not too far off in P4.

The Red Bulls took P5 and P6 in a weekend where they always looked more off pace than usual, largely down to a lack of power from the now slightly detuned Renault engine to aid reliability at altitude. The battle for best of the rest was won by Felipe Massa as he produced a brilliant drive in his last Brazilian GP to hold off Alonso and take P7.

Qualifying began with a shockingly rare error by Lewis Hamilton as he lost the rear of the car in turn 6 and into the barriers he went. That left three drivers in contention for pole: Bottas and the two Ferrari drivers. Vettel was looking in good shape after their first attempts in Q3, but Bottas dug deep and managed to improve on his second run to take pole. Vettel, by his own admission, had admitted that he had left a bit of time on the table in turn 1 as he ‘chickened out’ and braked a few metres early. Time which did cost him pole, but he made up for it with his start so he and Ferrari won’t dwell on it too much.

The Autódromo José Carlos Pace is another one of those circuits where it’s vital for the teams to find a compromise between downforce, drag, and straight line speed. The two long straights in Sector 1 and Sector 3 benefit from a high straight line speed, but the tight and twisty Sector 2 with a couple of high speed corners benefit from more downforce which usually adds drag, reducing straight line speed. A delicate balance needs to be struck to be competitive in both qualifying and the race, and since it’s difficult to overtake on this circuit, finding this balance is a tough challenge for the teams as they have to ensure their race setup doesn’t hinder them in qualifying.



Using telemetry charts, I’m going to go through and analyse four different cases to investigate the differences between the teams and drivers:

Bottas vs Vettel Bottas vs Verstappen Bottas vs Alonso Bottas vs Perez

All laps are Q3 unless stated otherwise. The charts are fairly simple. Each driver has the velocity plotted against distance. Sadly besides Bottas vs Perez there are no throttle and brake traces this time as I was unable to find onboard videos with this data. The time delta is also plotted comparing the first driver in the legend against the second. In the first chart below, the time delta is comparing Bottas’ lap against Vettel, so if the value is positive Vettel is slower and behind Bottas.

Please see the introduction of this post for an insight into telemetry and the limitations of the charts presented here. The code and data files are available on github.

Bottas vs Vettel

The battle for pole position was somewhat an inverted foreshadowing of the race. Closely fought between Bottas and Vettel, with Bottas triumphant on the Saturday and Vettel on the Sunday when it matters most. The laps themselves also went as expected, Mercedes were stronger in Sectors 1 and 3, and Ferrari were stronger in Sector 2.

Sector 1 starts off with Bottas having a 3-4kph advantage so he is already a 0.025s up before braking for turn 1. Vettel does brake a few metres later, but his top speed before braking is lower so both drivers are likely on the limit here. Bottas does carry 6-7kph more apex speed through turn 1 giving him a further half a tenth over Vettel, but he loses some of this through turns 2 and 3 as Vettel gets better traction and thus acceleration off turn 1, allowing him to carry more speed through turns 2 and 3. Vettel can’t maintain this small speed advantage on the long straight to turn 4 for a couple of reasons: the Ferrari doesn’t quite have the grunt of the Mercedes PU although it’s not far off, and their car also has a higher drag which hurts exponentially as the speed ramps up. If you look at the time delta trace from 600-1300m you can see how initially Vettel is gaining on Bottas, but after 400m or so Bottas starts to pull away. It’s at 300kph+ where the drag, even with DRS, and power really start to have a significant effect. At the end of sector 1 Bottas is just over half a tenth up.

Moving onto the more interesting sector 2, through turn 4 both are relatively even, but Vettel gets fantastic drive on corner exit and into turn 5, so he gains half a tenth on Bottas before the high speed turns 6 & 7. Before braking for turn 6, there is a noticeable speed differential of ~7kph. This is a good insight into how power and drag combine to affect the two cars as this is not a DRS zone, and you can see that the two traces start to diverge at ~280kph – this is 20kph lower than with DRS in Sector 1.

Turns 6 and 7 are high speed corners and Vettel in his Ferrari, as expected with its greater downforce, carries greater apex speed here. Vettel for the first time in the lap goes ahead at this point. It’s short-lived, however, as Bottas is quicker through the tight hairpin of turn 8, largely by carrying more speed into the corner. Vettel does get a strong exit and is much better through the long, awkward turn 9. He brakes later, carries more apex speed and gets on the power earlier, whereas Bottas in the Mercedes does the opposite, but the net time loss to Vettel was only under half a tenth. It was turn 8 where Bottas really gained a lot.

Turn 10 follows a similar pattern to turn 8 (and turn 1), with Vettel carrying less apex speed, but getting much stronger exits. Turn 9 follows immediately after turn 8, so Vettel wasn’t able to maximise his exit, but just like turn 1 it’s very clear here as he gains just over half a tenth on Bottas, so that at the end of Sector 2 Vettel is a just a few thousandths ahead. All to play for in Sector 3.

There’s only one corner here, but the exit is so so important as a long full throttle stretch almost a kilometre long follows thereafter. Turn 12 is where Bottas got pole position as he carries more apex speed and gets a decent enough exit to go just over half a tenth faster than Vettel through the corner. Vettel gets a much better exit than Bottas, so initially on the run down to the finish line he starts gaining on Bottas, but just like what happened between turns 3 & 4, as soon as the speed gets around the 300kph mark Ferrari start losing out as they simply don’t have the same top end acceleration as Mercedes.

Bottas vs Verstappen

After a competitive showing in Mexico, Red Bull returned to their status quo in qualifying at Interlagos; not in contention for pole, but easily ahead of the midfield. It was Verstappen who delivered a great lap as Ricciardo struggled to find a good balance, but he was still six tenths off pole – a large margin on such a short lap in terms of laptime. Red Bull put it largely down to their engine and said it cost them at least half a second, so lets have a look where they actually lost time and see how accurate their public figure was.

In Sector 1, Verstappen was similar to Vettel. Slower apex speed through turn 1, and quicker through turns 2 & 3 thanks to a better exit than Bottas. This is perhaps in part due to both Verstappen and Vettel taking tighter lines in turn 1 to set up turns 2 & 3 better. Verstappen only loses ~0.050s through turn 1-3, but finishes the sector almost 0.3s down losing 0.250s on the straights.

Through turn 4 both cars are fairly even, with Verstappen marginally faster, but he starts to lose time again to Bottas on the straight to turn 6. Note the difference in speed before braking here (DRS off) compared to before turn 4 (DRS on) is only up by 2-3kph, whereas in Ferrari’s case it was up 6-7kph. This indicates that Ferrari likely has a draggier setup than Red Bull around this circuit.

Red Bull and Verstappen have a completely different approach to turns 6 & 7 than Bottas (and Vettel). Instead of braking for turn 6 and accelerating through turn 7, Verstappen focuses more on maintaining momentum throughout the corners to minimise the distance he needs to accelerate from the exit of turn 7 to turn 8. My suspicion is that this approach is likely due to their power deficit. Neither driver gains or loses time through 6 & 7 though; two different styles but with identical results. Fascinating.

Verstappen comes back at Bottas through turns 8 & 9, gaining almost a tenth over the Finn, again highlighting the strength of the Red Bull chassis. Through turn 10 Verstappen loses half a tenth due to a lower apex speed and similar exit to Bottas. The overall time loss in Sector 2 was approx 0.1-0.125s, almost all of which was lost in the straights. These straight are shorter than the other two sectors, but they do add up.

Through turn 12 they are once again fairly equal; Bottas is slightly faster, but the main time loss for Verstappen is the long straight to the finish line where he loses a further 0.2s. So the overall time loss is between 0.45-0.50s, and given that the speed differentials with and without DRS relative to Mercedes are similar, I think it’s safe to say that almost all of the half a second loss is down to power. It’s important to remember that Renault had detuned their engine for Brazil too after Mexico raised their reliability and component supply concerns. So the normal Renault engine is not 0.5s down on Mercedes, the detuned one is.

Bottas vs Alonso

Alonso produced a wonderful lap by his high standards to put the McLaren in P7, narrowly missing out on first of the best of the rest to Perez by a few thousandths. McLaren don’t want to be fighting for P7 though, so the real test is how they compare against the front runners where they were 1.3s off the pace. A large part of that deficit is the Honda engine, and McLaren and Alonso claim that their chassis is up there with the best, but how much truth is there to this?

There’s no need to go sector by sector as a quick skim of the McLaren’s trace exhibits similar characteristics to both the Ferrari and Red Bull. There are a couple points of interest, mainly at turns 6 & 7. The first is that Alonso’s trace through these corners is similar to Vettel’s and Bottas’: brake for turn 6, and power through turn 7. Both the Ferrari and McLaren clearly running more downforce as shown by the greater apex speed by almost 10kph for Alonso.

I suspected that Red Bull and Verstappen’s different approach (emphasis on maintaining momentum and minimising acceleration into turn 8) might be due to their lack of power, but the Honda engine is even weaker than the Renault, so that argument doesn’t really hold. It is perhaps then due to car balance and handling characteristics, where the Red Bull has a more stable rear allowing the driver to throw the car into the corner and know that rear can handle it.

The second point of interest is the difference in speed relative to Mercedes with and without DRS. The latter is approx 6-7kph greater than the former, indicating the McLaren may have similar drag characteristics to the Ferrari.

Both Bottas and Alonso are close through all corners, there really isn’t much between them at all. The time loss on the straights totals to ~1.3s (0.5s in Sector 1, 0.35s in Sector 2, and 0.45s in Sector 3), which reinforces the observation that the two were almost identical through the corners, and the claim by Alonso that the chassis is up there with the front runners. It’s perhaps not quite on the level of Ferrari/Red Bull, but it very well could be if McLaren are compromising their wing levels to compensate for their power deficit.

Bottas vs Perez

Force India’s Sergio Perez was best of the rest in qualifying, but even with the Mercedes PU his laptime was a large 1.3s off the pace. If we assume equal power output from the PU, then all the differences will be down to chassis and driver. Throttle traces here will also help understand where Force India is lacking performance.

Looking at the trace overall, there is a visible lack of straight line speed on the straights. If engine power is the same then the main contributing factor will be aerodynamic drag, but it’s not that simple. The corner exit speeds for Perez are often lower the Bottas’ and this will also affect his top speed at the end of straights. The differences will be down to a combination of the two, but with perhaps slightly more emphasis on drag.

Drag usually comes at the cost of more downforce (it would be silly to add drag without adding downforce), so if Force India did run more downforce than they usually do at the expense of drag, then they’re still lacking a significant amount at high speed as evidenced by apex speeds in turns 6 & 7. The overall car balance does look good as through 6 & 7 Perez brakes less and can begin to get on the power much earlier and increase his throttle as the grip starts coming back. Bottas on the other hand has to be more patient and wait for the car to settle, but once it does he can apply throttle at a greater rate. He still has to lift a little through turn 7 (Perez is flat) so the car is still likely a bit unstable. Turns 1, 8, 9, and 10 also show similar attributes and indicate good low speed downforce and traction characteristics on the Force India, likely largely due to their higher rake angle than Mercedes.