F1 Anti-Lift Rear Suspension: Pitfalls and Problems

The decision was eventually made by Mercedes to discontinue using its rear suspension system, which had been variably implemented on its Formula 1 vehicle since its debut at Imola, at the Hungarian Grand Prix. While not explicitly cited as the reason for the team’s overall decline in performance, the updated suspension was viewed as a hindering factor in the further development and comprehension of its W16.

It is understood that the purpose of the system was to diminish the elevation of the rear axle under pressure. The rationale behind this is that the force exerted on the rear tires remains considerably more consistent, thereby maintaining the undercarriage at a stable height to produce a uniform level of aerodynamic grip.

The system was initially introduced at Imola, subsequently removed from the vehicle at Barcelona and Monaco, and then reinstated at Montreal. At the Canadian race, Mercedes achieved its first (and thus far, only) victory of the season, attributed to George Russell’s exceptional performance in Montreal.

Andrew Shovlin, Mercedes’ trackside engineering director, asserts that the circumstances in Montreal concealed some of the stability challenges that have become noticeable in recent races. This arguably prolonged the choice to permanently abandon it, until the team resolved to remove it from the vehicle at the Hungaroring.

Other teams, including Ferrari and McLaren, have opted for a suspension system with pronounced anti-lift attributes. He elaborated in Hungary that even designing a rear suspension system in conjunction with a new gearbox (which houses the attachment points for suspension mountings) is inherently a matter of compromise – and this compromise is intensified by developing a new system for an existing gearbox design.

“The truth is, even if you’re designing a suspension and gearbox with a completely clean slate, it is an immense compromise between where the aerodynamicists want to position all the legs, the various flexibilities, the kinematic properties, where the roll centers are… and it is actually impossible to set everything precisely where you want it to be,” Shovlin clarified.

Toto Wolff, Mercedes, Andrew Shovlin, Mercedes

Photo by: Peter Fox / Getty Images

“So the whole situation is a concession, and that concession is more severe when you’re implementing it to an existing gearbox and an existing suspension – and the budget limitations imply that you cannot simply discard everything and begin anew.

“The compromises that we might have encountered could have been quite different from those that Ferrari or McLaren experienced, so it’s certainly delving into the subtle specifics. McLaren has evidently achieved significant success with it, but it’s not challenging to perceive how particular aspects can mislead you.”

In F1’s preceding period, where the floors were largely uniform except for the diffuser at the rear end, suspension configurations were generally firmly established; teams typically utilized a push-rod front suspension and pull-rod rear configuration.

The suspension systems themselves could be modified, with some later designs providing some degree of adaptability at greater steering angles to maintain the car’s front end low for immediate aerodynamic grip retention, but this was perhaps a minor adjustment to an otherwise-standard solution.

However, the ground-effect floors are delicate and necessitate consistent ride heights to function across a spectrum of cornering conditions. Although 1981’s Lotus 88 is (by contemporary standards) a rudimentary illustration of this, the requirements of maintaining the Venturi tunnels at a consistent level were understood even then. In this instance, the ‘twin-chassis’ 88 had a softly sprung inner chassis, and the outer chassis containing the tunnels was stiffly sprung to guarantee the ground-effect floor maintained a consistent height.

The modern anti-lift rear suspension strategy operates on a somewhat similar principle of maintaining the floor at a stable ride height. Further developing the aerodynamic interface of the floor only yields marginal enhancements at this stage, and thus teams have been eager to explore deeply into the kinematics involved to ensure the floors operate at their optimal level for extended periods.

Elio de Angelis, Lotus 88-Ford Cosworth

Photo by: Sutton Images

Shovlin clarified that external considerations have also influenced the decisions to venture further into suspension development, particularly as teams have been keen to utilize their wind tunnel allowances with the forthcoming 2026 vehicles.

“I believe it’s the degree to which you extend it,” he stated, “not so much that numerous teams may well have had a percentage of anti-lift in the car, but what you could observe that McLaren was implementing was pushing that exceptionally hard.

“The reality is that as the aerodynamic enhancements from the regulations are beginning to diminish. You’re discovering increasingly smaller performance gains.

“The additional factor is that teams must transition their wind tunnels to next year’s regulations. I believe that naturally implies that you begin exploring other areas that you might not have investigated as thoroughly before.

“What you can derive from the vehicle dynamics aspect is that it’s logical that towards the conclusion of a set of regulations you begin examining areas that you might not have because the standard fundamentals of aerodynamic development begin to dry up.”