The 12 months 2025 marks the ultimate System 1 season for energy models launched with the 2014 rules. Regardless of a protracted 12-season interval, together with solely 9 years of unrestricted growth earlier than the freeze in 2022, the technical cycle concludes with out absolute convergence, with two equally legitimate philosophies. Till the top, Ferrari has remained the only staunch supporter of the compact turbocharger engine, resisting the cut up turbo embraced by Mercedes, Honda, and Renault. Nonetheless, this alternative has left no regrets.
The cut up turbo
Mercedes was the primary producer to introduce the cut up turbo structure for hybrid energy models. This resolution separates the turbine, powered by scorching exhaust gases, from the compressor, which compresses the air getting into the engine. A rotating shaft connects the 2 elements, with the MGU-H positioned in between. The MGU-H is an electrical motor pushed by the turbine to recharge power, however it may additionally carry out work to speed up the compressor.
Honda adopted Mercedes, introducing a cut up turbo structure, which Renault later adopted with its 2022 energy unit. That very same 12 months, it was speculated that Ferrari may additionally undertake this design, however the Maranello technicians and engineers selected to proceed with its philosophy. “In our structure, the MGU-H is mounted in entrance of the turbocharger,” defined Enrico Gualtieri, head of Ferrari’s engine division, in 2023. “Through the years, we determined to take care of this resolution, which is uncommon in comparison with our opponents. The selection was to maintain a compact turbo-MGU-H meeting relatively than separating them, permitting your entire unit to suit inside the V of the engine between the 2 cylinder banks.”
The benefits
In a 2021 interview with the Ialian media, then Honda F1 technical director Toyoharu Tanabe mentioned the choice to undertake the cut up turbo: “We gained expertise with the compact resolution earlier than transferring to the configuration with separated turbine and compressor, as we at Honda profit from this setup. We realized loads from each the earlier and the present designs. Maybe there are benefits to the compact turbocharger, however since we by no means went again to that resolution, I can’t say for sure. Nonetheless, the present structure is likely one of the finest compromises.”
The choice for one idea over one other depends upon the facets chosen to be prioritized, aiming for the absolute best compromise between weight, measurement, and engine efficiency. The cut up turbo, for instance, separates the turbine and compressor, putting them exterior the engine block. This association permits the connecting shaft and the MGU-H to be housed between the 2 cylinder banks, reducing your entire turbocharger meeting.
On one hand, the cut up turbo helps decrease the middle of gravity whereas guaranteeing compact dimensions and better freedom for the aerodynamics division in designing the automobile’s bodywork. Nonetheless, the equation additionally contains the shapes of the consumption and exhaust ducts, the air and gasoline strain losses inside them, the usable engine energy, and {the electrical} power that may be regenerated via the MGU-H. “From the attitude of energy unit efficiency, we’d like a sure stage of energy obtained via power regeneration,” Tanabe defined in 2021. “The cut up turbo package deal might additionally influence aerodynamics, however total, the benefits when it comes to energy unit competitiveness are better, which is why we selected this resolution.”
Ferrari’s philosophy
Through the years, Maranello’s engine division has repeatedly explored the cut up turbo structure however by no means discovered the identical benefits as its rivals, persevering with as a substitute with its personal path. That is additionally as a consequence of totally different selections concerning the compressor, with Ferrari choosing a smaller compressor in comparison with opponents, prioritizing decrease weight, ease of attaining excessive rotational speeds, and higher response at low revs. The compact measurement allowed—and nonetheless permits—Ferrari to suit the turbocharger meeting inside the area between the cylinder banks, providing related advantages to the cut up turbo, a minimum of when it comes to measurement and aerodynamics.
The duality between the 2 philosophies is, nonetheless, set to finish within the 2026 System 1 championship. The upcoming rules, moreover eradicating the MGU-H, impose most and minimal diameters for the turbine and compressor and, most significantly, restrict the space between the 2 elements to 175 mm. The cut up turbo is ready to vanish from System 1 after fascinating all producers from 2014 to immediately, although it by no means managed to persuade Ferrari.