5 Series E60 530d (M57T2) SAL
In 2-stage turbocharging, the two turbochargers work hand-in-hand.
Operation at low load and low speed:
The lines bypassing the small compressor and the small turbine are sealed. The exhaust gas first drives the
small turbine, then the large one.
On the fresh-air side, the large compressor compresses the fresh air first, then the small compressor.
The small compressor does the main part of the compression work.
This ensures very good response characteristics. This situation is supported by the fact that the large
compressor precompresses the fresh air.
Operation at medium load and medium speed:
As speed increases, the large turbocharger becomes gradually more important. The engine reaches its peak
torque of 580 Nm from 1750 rpm.
The turbine control valve splits the exhaust flow between the two turbines. The variable setting of the turbine
control valve allows the different operating ranges to be realised. At the same time, the boost pressure is
regulated.
Operation at high load and high speed:
The small turbine and small compressor are bypassed when the compressor bypass plate and turbine control
valve are fully open.
This allows the large turbocharger to deliver large amounts of air without the small turbocharger restricting the
airflow.
The compression work is then done entirely by the large compressor. The engine reaches its maximum power
output of 210 kW/286 hp at 4400 rpm.
Notes for service staff
Service staff should note the following points:
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General note: [more ...]
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Diagnosis: ---
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Encoding/programming: ---
Subject to change.
SBT 2-stage turbocharging E60, E61, E83, E90, E91, E92 M57TU TOP, M57TU2 TOP
BMW AG - TIS
22.02.2013 13:40
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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