How long should you wait to turn off the engine after driving a turbocharged car at high speed?

[StMalachi]

No need to wait. When driving on highways, the engine operates under non-ideal conditions, running at medium to low loads with relatively low temperatures, so no cooling is required. Moreover, modern vehicles are equipped with delayed cooling water pumps that continue to dissipate heat even after the engine is turned off. For more information on turbocharging, see below: Principle: Without changing the cylinder volume, turbocharging increases the intake air volume, allowing more fuel to be burned to generate greater power. Therefore, when the turbocharger builds positive pressure, the vehicle's acceleration becomes more powerful. Turbocharged engines do not maintain positive pressure all the time; building pressure when there is no power demand would only result in unnecessary fuel consumption. Thus, when a turbocharged engine maintains a steady speed, the turbocharger acts merely as a follower device and does not build pressure. After prolonged high-load operation, the turbocharger's housing can reach temperatures close to a thousand degrees, continuously transferring heat to the intermediate housing, where the circulating engine oil carries the heat away.