The wastegate is a key component of every turbocharger. But what are internal and external wastegates and what purpose do they serve?
Gearheads who want their car to go faster need more horsepower, and that can be achieved with a turbocharged engine. Turbochargers are installed to produce more power by increasing the density of the air that goes into the engine’s cylinders. This burns more fuel, creating more power. Turbocharged engines come with a variety of components that ensure this extra horsepower doesn’t come at a cost since this modification can stress the engine and its parts. One of those key components is the wastegate, which controls the amount of exhaust gas going into the turbocharger — and the amount of boost it makes.
There are two types of wastegates: Internal and external. Both ensure exhaust gas bypasses the turbocharger and control the boost level to protect the engine and the turbocharger from damage. An internal wastegate is most common, found right ahead of the turbocharger’s turbine wheel. The internal wastegate’s valve opens and vents some of the produced exhaust gas when the intake charge reaches a specific PSI.
