McLaren 540C, Product Manual

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39
SPORTS SERIES PRODUCT GUIDE /
Engine & Gearbox Control
01 Description
New engine and gearbox control strategy.
02 Customer Benefits
Performance
Faster gearshifts are achieved through a number of new
control strategies, focusing on the rate of engine speed
transitions. New advanced throttle control during shifts
ramps up or down engine speed with greater urgency.
Cylinder-cut first seen on the 650S for up shifts has been
updated to activate on both up shifts and downshifts, now
utilising the engine ignition control it can improve gear
change times, especially on the downshift.
Refinement
In order to optimise the match between the engine speed,
road speed and acceleration, an new control strategy has
been implemented which enhances refinement. On pull-
away, the interaction between the engine control and the
gearbox has been completely restructured (master and
slave). In the McLaren Sports Series 20% more signals are
sent (48 as opposed to 40 every 10 milliseconds)
POWERTRAIN
meaning that the driver feels an even greater sense of harmony
between throttle, engine and gearbox.
Refinement has also been improved once the vehicle is in
motion (during accelerator tip and tip out) . The software is
designed to use a new algorithm to predict and thus eliminate
any powertrain (engine and gearbox) oscillations. As part of the
new faster gear shift times this ensures that no rocking or ‘jerk’
upsets the vehicle balance or disturbs the occupants.
Normal / Sport / Track Modes
The sense of engagement with the car during gearshift as well
as when accelerating and decelerating is key in delivering the
exhilarating feel of the McLaren Sports Series. It is also key to
deliver this exhilaration throughout the performance envelope
of the car, not just when the driver might be seeking the fastest
lap time, for example.
To provide the greatest sense of interaction and performance
during all driving situations three control strategies have been
developed; Powershift, Cylinder Cut and Inertia Push.