Volkswagen Passat '97, Руководство пользователя

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The principle of variable valve timing:
Performance position
In the “Performance” position, the lower section
of the chain is short while the upper one is long.
The inlet valve closes late.
The rapid air flow within the intake manifold
ensures that the cylinder charge is high. The
engine is thus able to develop high output at high
speeds.
Torque position
Moving the variable valve timer down shortens
the upper chain section and lengthens the lower
one.
The inlet camshafts therefore rotate in relation
to the exhaust camshaft. The exhaust camshaft
cannot rotate at the same time, since it is
restrained by the toothed belt.
The inlet valve closes early.
In this position, high torque is produced in the
lower and medium speed ranges.
The exhaust camshaft is driven by the
crankshaft by means of a toothed belt.
The inlet camshaft is driven by the exhaust
camshaft by means of a chain. With variable valve timing, the opening times
of the inlet valves are adjusted depending on
engine speed. The drive chain therefore turns
the inlet camshaft.
Inlet camshaft Exhaust camshaft
Variable valve timer
SSP 192/081
SSP 192/080