Integrated Exhaust Manifold (IEM)
E203665
2
4
3
1
Exhaust passage
1
Coolant passage
2
Integrated Exhaust manifold (IEM)
3
Cylinder head
4
The turbocharger is mounted to an Integrated Exhaust
Manifold (IEM) positioning it closer to the cylinder
head exhaust ports for better response. The exhaust that
flows from the inner and outer pairs of cylinders are
kept separate as they flow into the two scrolls of the
turbocharger. Separating the exhaust pulses until they
reach the turbine wheel minimizes the backflow into
the next pulse, which provides a more efficient delivery
of exhaust gas energy to the turbine wheel.
The result is quicker response, improved efficiency and
better scavenging through valve overlap. The IEM is
cooled by engine coolant flowing throught it.
Service Training
42
Lesson 3 – Powertrain
Turbocharger
