How the Mercedes gearbox has slowed down Aston Martin

Jaden Diaz
28/03/2023

It is now well established that Aston Martin is F1’s ‘surprise’ of 2023. Unlike Ferrari, the Silverstone-based team was able to translate its performance from the simulator to the track.

What Aston Martin has done in the last year is very impressive. Just last season, in the first four races of 2022, the AMR22 was two seconds slower than the RB18.

This gap has been cut down to just half a second per lap in the last few races, partly thanks to a better understanding of the last year’s B-spec AMR22, introduced in Barcelona.

An improvement of 9 tenths was made over winter, which has positioned the British squad as the nearest challenger to Red Bull, currently faster than the established front-runners Mercedes and Ferrari.

Aston Martin’s suspension is similar to Red Bull’s

Two consecutive podiums put Fernando Alonso 14 points behind Max Verstappen in the standings. In both Saudi Arabia and Bahrain, Alonso was the closest to the Red Bull duo in race pace:

“The most important thing is to see that the car was also so strong in Jeddah, as we were second team,” said Alonso post-race.

“We were much stronger than Ferrari, and we managed to control Mercedes. All this was unthinkable before the weekend.

“In Bahrain, we had an advantage in terms of degradation while Jeddah showed that the car raw pace because we were faster than the others – and this was not because of tire management,” said the Spaniard.

Red Bull RB19 front sospension

La sospensione anteriore della Red Bull RB19 è molto anti-dive con la scopo di mantenere la vettura ad una altezza costante dal suolo.

What was the gap to Red Bull? Looking at the last stint on the hard tires in Jeddah, the deficit was about six-tenths per lap – similar to Bahrain. However, it should be noted Red Bull managed their pace and used very conservative power unit mappings.

The Silverstone-based squad has stressed that the AMR23 is entirely made by Aston Martin and that, if anything, their car is most similar to Mercedes in terms of components – since Aston buys the rear of its car from the Silver Arrows.

More broadly speaking, Aston cannot deny where much of their aerodynamic concept , including their underbody and front suspension, comes from.

In this sense, although the RB19 uses a pull-rod front suspension and Aston Martin uses a push-rod, the overall geometry in this area is clearly inspired by Red Bull.

Regarding aerodynamic stability, the AMR23’s geometry is more relevant than its rod type. Both Aston Martin and Red Bull’s front suspensions are very anti-dive , meaning the front arm of the two triangles is positioned much higher than at the rear.

Ferrari has also tried to be more aggressive with its front suspension, as seen with the SF-23’s front far less conventional design compared to last season. This allows the front suspension to significantly limit the transfer of load to the front, ensuring aerodynamic stability.

However, excessive anti-dive has its drawbacks. The main weakness is an inability to absorb bumps, resulting in instability when braking.

The key for Red Bull and Aston Martin is in this area and how they have managed to eliminate the possible instability caused by an aggressive anti-dive front suspension.

According to a rival engineer, a very anti-dive front suspension is an important factor in not triggering porpoising, as there is less front-end instability.

It is no coincidence that both Red Bull and Aston Martin have not shown any issues with porpoising, even though the two cars have two completely different rears.

Aston Martin has a less efficient diffuser because of the Mercedes gearbox

The aerodynamic concept of the Aston Martin AMR23, as previously mentioned, has many similarities to the Red Bull RB18.

“Aston Martin? I‘m happy that the old Red Bull is still going strong,” joked post-Bahrain Christian Horner.

Red Bull’s biggest strength was never its peak downforce level, but instead, its ability to maintain a high level of stability with different ground clearances –  as well as aerodynamic efficiency.

Simply put, the RB18 could run higher without losing too much downforce, as opposed to Ferrari and Mercedes, which opted for lower ride heights.

The AMR23 has a rear end with similar characteristics to the RB18, allowing Alonso and Stroll to generate significant downforce levels.

Aston Martin AMR23 vs Red Bull RB19 rear view

Rear area comparison Aston Martin & Red Bull – The AMR23 has a stronger and stronger wing than the RB19.

However, the Silverstone-made car lacks the aerodynamic efficiency and top speed of Red Bull’s RB19. This is where the rears of the two cars come into play.

Aston cannot be a copy of the RB18 because their rear end is purchased entirely from Mercedes. Their gearbox and rear suspension are the same as those used on the W14.

In terms of transmission, there are very important differences between the Red Bull and Mercedes specifications.

The Mercedes specification is bulkier in the area closest to the floor, which limits airflow through the AMR23’s diffuser. This area is designed for a car with ultra-compact bodywork like the W14, as seen with the Mercedes ‘zeropods.’

Having a less efficient diffuser means the AMR23 needs more rear wing to compensate, which generates more drag.

In the two qualifying sessions so far this season, Alonso lost about half a second in the straights, more than 10 km/h slower in the speed trap compared to the RB19s in Jeddah.

This cannot be solved immediately, in part due to the budget cap, with Aston Martin choosing to introduce a very similar rear wing in Jeddah compared to Bahrain.

Only a slight modification to the AMR23’s DRS flap was introduced in Saudi Arabia, designed to reduce its resistance. However, a lower-loaded winger will arrive in Baku, which the English team is trying to anticipate for the Australian GP.

Meanwhile, Red Bull has focused solely on aerodynamics when designing the RB19’s transmission, with an extremely small lower section.

This has resulted in some reliability problems with its drive shafts and the transmission more generally, with two having already mounted two power units on both RB19s in the first two rounds of the season. 

This compact size is also made possible by the team’s use of the rear push-rod layout.

As such, the internal part of the suspension has been moved much higher – compared to the classic pull rod used instead by Mercedes, and therefore Aston Martin, which has them in the lower part.

Author: Piergiuseppe Donadoni

Translation: Jaden Diaz-Ndisang

Autore

SEGUICI SU

Podcast