The subject of rake and the impact of the 2021 Formula 1 rule changes rumbles on, with the debate about the relative merits of high versus low rake one of the defining factors of the season.
But sometimes it’s not as simple as that, as I’d suggest there are three groups of teams in terms of approach. We took the opportunity over the Barcelona weekend to get a clear side-on shot of each car at the entry to the Turn 10 left-hander.
The cars are all travelling at more or less the same speed into this medium-speed corner, so this is representative image of the rake at corner entry rather than simply being a stationary shot in the pitlane.
The rake simply describes the difference in the ride height between the front and the rear of the car. The front of the cars all run at the minimum possible ride height, so high rake means the car is higher at the rear with a steeper incline of the floor from front to rear, and low rake means the car runs flatter.
I have put a red line along the lower edge of the floor on the Mercedes. This is on what is called the reference plane in the regulations, so in effect my line is the bottom of the underfloor plank. I have then transposed that line at the same angle onto all the other cars.
Its positioning is relative to the leading edge of the floor tongue as this is, in reality, the lowest part of the car relative to the track. This shows very clearly that there are three levels of rake used across the teams.
Minimum rake: Mercedes and Aston Martin
Medium rake: McLaren, Ferrari, Alpine, Alfa Romeo and Haas
High rake: Red Bull, AlphaTauri and Williams
With the front ride heights being very similar, the differences we see between Mercedes and Red Bull’s rear ride height are probably about 40-50 millimetres with the other teams other than Aston Martin fitting in between them somewhere.
Over the last few years, most teams other than Mercedes have tried to go the Red Bull route of high rake. Some have succeeded, some have failed and some tried it but appeared to not really understand why they were trying it.
It’s interesting to note that what you might call brother, sister, uncle, neighbour or twinned teams take very similar approaches when you look at Mercedes/Aston Martin and Red Bull/AlphaTauri. Only Williams really stands out as following a trend without a close relationship with another team.
There are lots of things that influence a car’s concept and you don’t just head into the windtunnel with a big rectangular block of clay and start carving. You start from a concept and refine everything around that.
If you change direction dramatically, you can very easily put yourself back three months, so you need to believe in what you are trying to create and not keep changing direction otherwise you will get nowhere.
Aston Martin is an example of a team that changed direction. Up until last season, it used the Red Bull high-rake concept with reasonable success. Then a controversial change to the low-rake Mercedes concept for 2020 seemed to be the correct direction. But it is suffering more in 2021 than most.
While there is probably 40-50mm between the different concepts, there is also a middle way, which is where most teams have ended up. In the windtunnel, you will test a range of ride heights that the car goes through on the track due to different speeds.
You will then be able to take that group of ride heights up, so the lowest ride height isn’t as low to the ground, and then see if your average downforce is better with the car higher or lower. You will then select the best height range to optimise everything around – low, high or somewhere in between.
The big question is, does the differing rake dictate the performance? The answer is emphatically no. It is only part of the jigsaw that makes up the concept of an F1 car, as there are many things that contribute to performance and each and every one is as important as any other.
The most important thing aerodynamically on a racing car is to manage the centre of pressure shift. All the downforce-producing components add up to the total load on the car and this is called the centre of pressure (CofP). You don’t want this load centre to move around the car needlessly or in the wrong direction.
As a very basic example of CofP management, as the car’s speed increases the front and rear ride height will get lower at around a 3:1 ratio. With this change in ride height, you want the CofP to slowly move rearwards. This can be achieved with the underfloor, diffuser and front wing characteristics – basically anything that changes its height by a big percentage relative to the track surface.
As Mercedes has shown, no matter what concept you have it’s about getting the best out of it week after week. You have to minimise your mistakes and always be there to pounce if and when others make those mistakes and as Lewis Hamilton showed in Barcelona he was right there when Red Bull fell asleep.
Comparing the pace of the cars based on their fastest time of the weekend both in terms of seconds and percentage shows who has lost the least relative to when F1 cars last ran in Barcelona in August 2020.
While this is just a snapshot of a moment in time, Barcelona is a circuit that has a bit of everything and where every team and driver has lots of experience so that makes it perhaps the most representative of the circuits F1 has been to this year.
BARCELONA PACE LOSSES 2020-2021
Yes, the circuit has changed slightly but it has changed for everyone so it gives a fair comparative picture. Given Haas is the team that has done the least development of its car compared to last year, largely focusing on adapting for the regulations, we can use this as a constant.
The figures suggest that Mercedes has still not really got on top of the enforced changes, but since it had such a comfortable advantage over everyone last year, they are still able to be right up there. Aston Martin didn’t have that luxury, so has dropped behind many of its midfield rivals.
The image below compares each team’s ultimate performance turned into a percentage and averaged out after the last four races of 2020 and the first four races of 2021 in this very entertaining season, in 2021 performance order. This shows the performance deficit to the front, so if you had been fastest over all four events the average deficit would have been zero.
TEAM PERFORMANCE, RACES 14-17 2020 v RACES 1-4 2021
The 2021 column shows what we are seeing every weekend – that the battle between Mercedes and Red Bull is nip and tuck. It’s the same between Ferrari and McLaren, Alpine and AlphaTauri,
Aston Martin is in a bit of no man’s land and Williams and Alfa Romeo are again very close with Haas bringing up the rear. Just to add to that, with the tools he has I think Mick Schumacher is doing a solid job. It’s never easy when you know that if everything goes well you are still going to qualify near the back.
In the delta column, it shows the only loser relative to the best performer is Aston Martin. That means the school report for it would read “must try harder”. While there are still complaints about the process that led to the rule change, teams just have to get their heads down and make the most of what they have got.
For Williams, it’s the other way around. Although one of its last four races in 2020 was without Saturday star George Russell, it still shows impressive advances. Mind you, being at the back means there is more low-hanging fruit available – in the sense that it’s easier to find performance than for those fighting over tenths at the front – before you need a ladder to reach it. Climbing up that ladder is when it becomes that bit more difficult.
Monaco, with its lack of run-off areas, is going to be another challenge. You pay for mistakes immediately there so to be fast you need 100% confidence that the car is going to do what you request it to do, lap after lap.
So far, I haven’t seen too many of this year’s cars with those characteristics. That perhaps suggests that whether you go to low, medium or high rake, the rule changes have had an impact on everyone.