BMW
Media
Information
5/2009
Page 32
Response even better than before, fuel consumption even lower.
VALVETRONIC has already proven its qualities in numerous BMW engines the
world over as a particularly effective technology providing even greater effi-
ciency. The big advantage of VALVETRONIC is the infinite control and adjust-
ment of valve stroke on the intake valves, making the throttle butterfly used in
former times superfluous. VALVETRONIC reduces throttle losses in the charge
cycle process to an absolute minimum and optimises engine response since
the air mass required to control the combustion process is masterminded in the
engine itself and not outside the power unit with the usual “dead” volume. This
ensures particularly efficient use of the energy contained in the fuel, developing
a very muscular torque curve and giving the engine optimum response.
In particular, the better response of a VALVETRONIC engine results from the
fact that underpressure under part load is only approximately 50 millibar, while
on a conventional engine up to 800 millibar of underpressure has to be set off.
On the BMW 535i Gran Turismo the VALVETRONIC functions have been
optimised again by a new adjuster complete with a fully integrated sensor
serving above all to make the adjustment process even faster than before.
Indeed, the inertia factor on the new adjuster is only one-tenth the figure on
the former model, serving to further improve engine response.
Responding smoothly, directly and immediately to the gas pedal, the new
straight-six is clearly the leader in its class also in this discipline. Maximum
torque of 400 Newton-metres/295 lb-ft, for example, comes at just 1,200 rpm.
Apart from the optimised VALVETRONIC control unit, the newly developed
turbocharger also contributes to this superiority, ensuring a particularly
spontaneous build-up of power since the ducts of three cylinders at a time are
separated from one another both in the exhaust manifold and the turbocharger.
In practice, this means particularly low exhaust gas counter-pressure at low
engine speeds, the double ducts then enabling the flow of gas to build up
greater dynamism in the exhaust manifold and powerfully drive the turbocharger
blades even at low engine speeds. Twin-scroll technology thus combines
the benefits of two turbochargers within one system. And now this principle
adapted to the BMW straight-six with its high standard of technology marks the
ongoing, consistent development of BMW’s turbocharged engines.
| Categories | BMW 5-Series Manuals, BMW Manuals |
|---|---|
| Tags | BMW 530d, BMW 535i, BMW 550i, BMW F07, BMW Gran Turismo, Brochure and Catalogue |
| Model Year | 2010 |
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| Copyright | Attribution Non-commercial |
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