BMW S58, Руководство пользователя

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S58�Engine
4.�Engine�Mechanical
16
S58�engine,�ventilation�bore�holes�in�the�crankcase
The�crankcase�has�drilled�longitudinal�ventilation�holes�(a).�Those�longitudinal�ventilation�holes
(a)�improve�pressure�equalization�between�the�oscillating�air�columns�created�by�the�up�and�down
movement�of�the�pistons.
In�addition,�adaptations�of�the�connections�to�the�two�exhaust�turbochargers,�were�necessary�for�the
oil�supply�and�coolant�cooling.
4.1.3.�Cylinder�head�gasket
In�contrast�with�the�B58TU�engine,�the�cylinder�head�gasket�in�the�S58�engine�is�made�up�of�4�layers
(3�layers�in�the�B58TU�engine)�because�the�combustion�pressure�is�higher�than�in�the�S58�engine.
Furthermore,�the�contact�faces�with�the�cylinder�head�and�cylinder�block�are�no�longer�fully�coated
but�instead�have�a�partial�screen�print�coating.�The�cylinder�head�gasket�has�been�adapted�to�the
crankcase�and�the�cylinder�head�in�terms�of�the�sealing�bead�pattern.