Beyond the turbo
The issue with race starts stems from the difficulty of getting the turbocharger up to a rotational speed high enough to compress the intake air and achieve sufficient combustion pressure. Until 2025, the electric MGU-H helped by directly accelerating and controlling the compressor’s speed. Now, however, the turbo relies solely on exhaust gases for its drive.
When the driver lifts off the throttle and engine revs drop, exhaust flow decreases. When the throttle is reapplied, the turbo must regain speed, creating a delay in engine response known as turbo lag. Managing this phenomenon has become one of the main engineering challenges of the new power unit era.
Engine manufacturers have had to choose between designing a larger turbo, prioritizing higher peak power at high speeds, or a smaller one. The impression is that Ferrari opted for the latter solution. A smaller, lighter compressor can spool up more quickly, reducing turbo lag and improving throttle response, particularly in low-speed corners and at race starts.
In reality, turbo lag duration depends on several additional factors, including the design of the plenums – the air boxes that collect compressed air from the turbo before distributing it to the cylinders. The larger the plenum, the more time the compressor needs to raise internal pressure, increasing response delay. Their importance is highlighted by the FIA’s recent regulatory adjustments concerning plenum design, ratified last December. This could indicate that one or more manufacturers experimented with innovative solutions in this area.
The other major change
Another restriction introduced for 2026 is the ban on variable-length intake trumpets. These are the ducts that channel air from the plenums to the individual cylinders. Inside them, pressure waves are generated and bounce back and forth at a frequency determined by their length.
The goal is to synchronize the arrival of these pressure waves with the opening of the cylinder valves, allowing higher-pressure air to enter the combustion chamber and improving efficiency. Until last year, engines used variable-length trumpets that could adapt to different engine speeds, tuning the pressure wave frequency accordingly.
This is no longer allowed. Engineers must now select a fixed geometry that represents a compromise between low-rev performance and high-speed power output. As a result, turbo size, plenum design, intake duct geometry and many other parameters all define the overall engine concept. Ferrari appears to have optimized its power unit for low-speed acceleration, including the critical launch phase.
The impact on lap time
A Formula 1 power unit is never designed in isolation. It is closely integrated with full-vehicle simulations, taking into account the expected cornering speeds and straight-line sections across the entire race calendar. Engineers analyze the average operating range of the engine and determine where optimization will deliver the greatest lap time benefit.
A power unit that favors acceleration may sacrifice some peak power, but it gains valuable time on corner exits and secures an advantage at the start. This approach is also intertwined with hybrid energy management. An engine that performs strongly at low speeds does not need as much electrical assistance to regain revs, allowing energy to be saved for phases where it is truly beneficial – when rear tire grip is no longer the limiting factor.
Ferrari’s engine strategy appears clear: prioritize drivability and acceleration. However, rival power unit manufacturers undoubtedly have their own concepts and performance cards yet to reveal as the 2026 Formula 1 season unfolds.
