Turbocharger

An exhaust-driven compressor that forces extra air into the engine.

Also called: turbo

What it means

Definition

Garrett, an OE turbocharger maker, describes the arrangement: turbos utilize exhaust gases to power a turbine wheel, which is connected via a shaft to a compressor wheel. The DOE adds what the compressor does — turbochargers are compressors that force additional air into the engine's cylinders, allowing more fuel to be injected as well. That is how a smaller engine can produce the output of a larger one.

Why a buyer cares

What it changes

It is a high-speed assembly fed by the engine's own oil supply, which makes oil service history more relevant on a turbocharged car than on a naturally aspirated one.

In practice

Where you meet it

In trim and engine badges, in listing spec lines, and on invoices where the turbo itself was serviced.

Two things that look alike

Not the same as

A supercharger does the same job but is driven mechanically off the engine rather than by exhaust gas.

Where this comes from

Sources

A research agent proposed a Garrett sentence citing 350,000 RPM; the page does not carry that sentence and the figure was dropped.