23
SSP 198/32
Charging
Two
water-cooled exhaust gas turbochargers
with wastegate are used for charging.
The charge pressure of both exhaust gas
turbochargers is controlled via the common
charge pressure control valve N75.
Advantages of the biturbo technology:
•
The exhaust gas turbocharger is smaller,
which means better response due its
reduced mass.
•
Higher charge pressure at low engine
speeds.
•
The exhaust gas turbochargers are located
outside the V-angle due to the high
temperatures they reach. This advantage of
this arrangement is that the intake air is not
heated up additionally and the sub-
assemblies are not subjected to so much
thermal stress.
•
Since the turbochargers are flanged
directly onto the exhaust manifold, the
exhaust gases travel less distance and
there is less temperature loss.
•
As a result, the catalytic converters are able
to heat up more quickly and the efficiency
of the exhaust gas turbocharger is
improved by the favourable air-flow.
Intake side of exhaust
gas turbocharger
Charge press. side
of exh. gas turbo-
charger
Exhaust manifold
to exhaust system
Pressure unit for actuating
wastegate flap
Control pressure from
solenoid valve for
charge pressure
control
The turbochargers must be replaced
in pairs
To maintain a synchronous air-flow
through the two chargers, it is
important to observe this instruction
to account for manufacturing
tolerances.
Service personnel are
not
permitted
to adjust the linkage to the wastegate
flap.
Turbine housing
Compressor housing
Summary of Contents for 2.7-litre V6 Biturbo
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