BMW S58, Руководство пользователя

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S58�Engine
5.�Valve�Gear
32
B58B30O1 S58B30T0
Camshaft�adjustment,�intake [crankshaft
degrees]
122.5–52.5 129.5–59.5
Camshaft�adjustment,�exhaust [crankshaft
degrees]
120–60 120–60
Opening�period
Intake�camshaft
[crankshaft
degrees]
258.2 273.5
Opening�period
Exhaust�camshaft
[crankshaft
degrees]
261.9 262.3
5.1.3.�Intake�and�exhaust�valves
The�valve�stem�of�the�intake�valve�has�a�diameter�of�4.92�mm.�For�the�exhaust�valve�the�diameter�is
5.92�mm.�The�reason�for�the�larger�diameter�is�that�the�exhaust�valve�is�hollow�and�has�a�sodium�filling.
In�addition,�the�valve�seat�of�the�exhaust�valve�is�armor-plated.
In�contrast�with�the�B58TU,�the�intake�valve�material�for�the�S58�engine,�has�been�upgraded�to�a
higher-quality�alloy�material�to�cope�with�the�thermal�and�higher�stress�on�the�engine.
5.1.4.�Valve�springs
Due�to�the�different�shaft�diameters�between�the�intake�and�exhaust�valves�the�valve�springs�are
different.
5.2.�Valvetronic
5.2.1.�VANOS
Overview
The�design�and�function�of�the�variable�camshaft�timing�system�on�the�S58�engine�is�the�same�as�on
the�B58TU�engine.�The�VANOS�system�had�already�been�optimized�by�virtue�of�the�single�chain�drive
on�the�B58TU�engine�in�comparison�with�the�B58�engine.�That�optimization�resulted�in�shorter�and
more�compact�adjusters.
The�camshaft�sprockets�of�the�VANOS�units�have�been�adapted�to�suit�the�single�bushed-roller�chain
on�the�S58�engine.
VANOS�solenoid�valve�actuators
The�VANOS�solenoid�valves�used�on�the�S58�engine�are�identical�to�those�on�the�B58TU�engine.