Throttle butterfly limit

In Simple Terms

F1 engines can only have one throttle butterfly (a valve that controls airflow) in the path between the turbo compressor and the engine cylinders. This prevents teams from using multiple throttles to gain an unfair advantage in controlling engine performance.

• Maximum of one butterfly or rotating barrel allowed in the air path from compressor outlet to cylinders
• Prevents teams from using multiple throttle valves to manipulate engine behavior
• Applies to the geometrical path of air exiting the compressor outlet
• A fundamental restriction on engine intake system design