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The 911 | Chassis
Vehicle yaw/
course deviation
Vehicle yaw/
course deviation
Correction to
vehicle course
deviation and
stabilization
Correction to
vehicle course
deviation and
stabilization
Oversteer without PSM
Understeer without PSM Understeer with PSM
the PSM intervention threshold is
raised to enable grea ter driver
involvement—particularly at
speeds of up to approxim ately
45 mph.
The integrated Anti-lock Brake
System (ABS) shorte ns the
braking dist ance even further
and the braking inputs are
smooth and preci se, thereby
enh ancing comfort.
An enhanced PSM system i s
characterized by two additional
functions: the precharging of the
brake system, and Brake Assist.
If the driver s uddenly releases
the accelerato r pedal, PSM
automatically readies the braking
system. With the braking system
having been precharged, the
brake pads are alre ady in light
contact with the brake discs.
Maximum braking power is
therefore achieved much sooner.
When sudden braking is
detected—i.e., if the pressu re
on the brake pedal exceeds a
predefined level—the Brake
A ssist function uses the PSM
hy draulics to apply maximum
brake pressure to all four wheel s.
If you want a purely active dri vin g
experience, you always have the
option to deactivate PSM. It is
automatically reactivate d, for
your safety, if e ither of t he front
wheels (in Sport mode, both of
the fr ont wheels) req uires
ABS assistanc e. The ABD
function, however, remains
active at all times.
In conclusi on , PSM offers a high
level of driving stab ility and
safety—and typical Porsche
agility at the same time.
Oversteer with PSM
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