BMW S58, Руководство пользователя

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S58�Engine
4.�Engine�Mechanical
27
Wrist�pin
The�wrist�pin�with�circlip�was�revised�accordingly�to�the�higher�requirements�in�the�S58�engine.
The�material�and�the�strength�were�adapted�to�satisfy�the�high-speed�concept.
A�so-called�wrist�pin�with�restricted�volume�change�with�23�mm�diameter�is�used.�The�wrist�pin�is
made�from�the�alloy�16MnCr5�and�then�case�hardened�(DLC�diamond-like�carbon).
4.3.�Camshaft�drive/chain�drive
The�entire�chain�drive�system�driving�the�camshafts�on�the�S58�engine�has�been�carried�over�from�the
N58TU�engine.�As�on�the�B58TU�engine,�the�composite�camshafts�are�driven�by�an�adapted�single
bushed-roller�chain�with�154�links.�The�tensioning�rail�is�a�carry-over�part�from�the�B58TU�engine,
while�the�bushed-roller�chain�itself�and�the�guide�rail�have�been�adapted�to�the�high-revving�concept
and�higher�power�of�the�S58�engine.