BMW S58, Руководство пользователя

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S58�Engine
8.�Intake�Air�and�Exhaust�System
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Index Explanation
1 Exhaust�manifold,�cylinders�4-6
2 Wastegate�valve,�control�rod,�cylinders�4-6
3 Oil�feed�line
4 Electrical�wastegate�valve�actuator,�cylinders�4-6
5 Clean�air�feed,�cylinders�4-6
6 Exhaust�manifold,�cylinders�1-3
7 Electrical�wastegate�valve�actuator,�cylinders�1-3
8 Clean�air�feed,�cylinders�1-3
9 Connection�for�the�charge�air�cooler,�cylinders�1-3
10 Coolant�connections
11 Oil�return
12 Wastegate�valve,�control�rod,�cylinders�1-3
13 Connection�for�the�exhaust�system
14 Connection�for�the�charge�air�cooler,�cylinders�4-6
The�S58�engine�has�a�twin-turbocharger�system�using�mono-scroll�turbochargers�as�also�used�on�the
S55�engine.�The�system�supplier�for�the�mono-scroll�turbocharger�assembly�on�the�S58�engine�is�the
MHI�Group.
8.2.3.�Electrical�wastegate�valve�actuator
The�S58�engine�uses�an�electric�wastegate�controller.�The�function�of�the�electric�wastegate�controller
on�the�S58�engine�is�the�same�as�on�the�BMW�AG�engines.
The�fundamental�advantages�of�the�electric�wastegate�controller�are:
• High�adjustment�speed
• Precise�charging�pressure�control
• High�closing�force,�thus�less�leakage�and�quicker�build-up�of�charging�pressure
• Complete�opening�of�the�wastegate�valve�possible.�This�supports�quick�heating�up�with�a�cold
catalytic�converter.
• Thus�lower�exhaust�emissions
• Fuel�economy
The�electric�wastegate�controller�is�controlled�directly�by�the�DME�control�unit�using�a�pulse-width
modulated�(PWM)�signal.
8.2.4.�Catalytic�converter
The�S58�engine�has�one�close-to-engine�catalytic�converter�per�cylinder�bank,�each�with�a�ceramic
monolith.