Ferrari recently made headlines during the Bahrain Formula 1 testing with an innovative design element on the SF-26 car. This clever adaptation, a blown exhaust flap, aims to enhance rear downforce, adding a competitive edge to the team's performance.
The unique solution was revealed gradually, but it took many by surprise on the opening day of the second Bahrain testing session. "This aerodynamic solution is designed to increase rear downforce on the SF-26," stated a team insider, underscoring the importance of the design choice.
The effectiveness of the blown exhaust flap hinges on maintaining the engine in higher revs, particularly in lower gears, while simultaneously recharging the car's battery. This is not a last-minute adjustment; the concept has been integrated into the car’s design from its early stages, indicating a long-term vision from the Scuderia team.
In the first session of the Bahrain test, Ferrari’s Charles Leclerc clocked the third-fastest time, just 0.280 seconds behind George Russell's Mercedes and Oscar Piastri's McLaren. “Lap times in pre-season testing are never definitive, but we’ve shown we can keep pace with the Mercedes-powered teams,” said Leclerc, highlighting the team's competitive status.
The overarching philosophy behind the SF-26 is becoming clearer with each test. Ferrari's close-knit departmental collaboration is a significant asset; Loic Serra, the chassis technical director, worked hand-in-hand with Enrico Gualtieri, the head of the power unit division, to develop this cutting-edge vehicle. "Our strength is in designing and building the car entirely within our factory," said Serra, emphasizing the integrated approach visible on the track.
The incorporation of a vertical flap ahead of the central exhaust outlet signifies a revival of the “monkey seat” concept, thanks to newly relaxed regulations that allow for such innovations. This device, designated internally as FTM, gained FIA approval since it complies with technical regulations. It was essential that the rear structure of the SF-26 allowed for this addition right from its initial design phase.
This central flap works in synergy with two diffuser extensions already present on the car. Developed by the aerodynamic team led by Diego Tondi, it redirects hot exhaust gases upward, enhancing rear wing efficiency and aiding airflow extraction from the diffuser.
As exhaust setups have evolved—particularly with the repositioning away from the floor as in earlier designs (2010-2013)—the traditional blown exhaust effect has diminished, particularly with the introduction of turbochargers. Yet, Ferrari is pursuing this route, driven by additional technical considerations. “For SF-26, we opted for a smaller Garrett turbocharger compared to our rivals,” explained a Ferrari engineer. This decision aims to combat turbo lag since traditional energy recovery from exhaust heat is no longer feasible without the MGU-H.
To counteract this, Ferrari strategically chose a smaller turbine to manage turbo lag while also relying on the gearbox to assist in battery recharge across the lap. The change included an instruction to drivers to occasionally shift into first gear, a practice diverging from previous strategies. “We wanted to ensure strong exhaust flow and maximize the aerodynamic benefits of our new flap,” said another team member.
This strategic choice is anything but a mere gimmick. It reflects Ferrari's meticulous engineering efforts and collaboration between various departments, resulting in a more dynamic car for the upcoming season. With the SF-26 still in the early testing phase, the anticipation grows: should fans expect further innovative developments as the testing continues?