Internal VS External wastegates, a brief overview.
Some time ago we talked about turbochargers, and the working principle behind them, but now we will discuss an integral part of any turbo setup: the wastegate.
A wastegate serves as a way to release excess exhaust pressure to avoid over boosting, there two kinds of wastegates: internal and external.
An internal wastegate is contained within the turbocharger’s turbine housing, and is in essence, a bypass valve that lets excess exhaust pressure go directly into the exhaust system, without spinning the turbine.
An external system is generally mounted in the exhaust manifold, and can either vent to the atmosphere, which is common in racing applications, or send its exhaust pressure to the exhaust system piping.
The video below discusses the advantages and disadvantages of both internal vs external wastegates.