Porsche 911 Turbo User Handbook Manual page 33

Braking system.
Always quick when you have to be slow.
The braking ability of the 911 Turbo design that is extremely rigid,
is every bit as impressive as its robust and lightweight to further
acceleration. Powerful, precise reduce unsprung mass. The
braking begins with four massive calipers feature six pistons in
discs. Measuring 13.78 in. (350 front and four in the rear. The
mm), each of the four discs is brakes are quick to apply and
internally vented and cross-drilled release, while the pedal travel
for maximum cooling under heavy is short, precise and consistent.
brake use and reliable braking in Air channels deliver cooling air
wet conditions. to keep the system fade-free.
Next come the calipers. A single Finally, we add the latest
block of aluminum forms the body driver's aids. Braking distances
of each monobloc caliper—a are reduced by the Anti-lock
Brake System (ABS) and the
electronic brake prefill and
brake assist systems, which
are integral to Porsche Stability
Management (PSM).
Standard brake unit
Porsche Ceramic
Composite Brake.
For the ultimate in high-performance
braking technology, the 911 Turbo
can be equipped with the optional
Porsche Ceramic Composite
Brake (PCCB) system.
The key components in PCCB are
the molded ceramic discs, which
are a larger 14.96 in. (380 mm)
at the front, and 13.78 in. (350
mm) at the rear. As a result of an
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extremely complex manufacturing
process, they are harder, more
resistant to high temperatures,
and only about half the weight
of grey cast-iron discs—three
reasons composite brakes are
widely used in today's most
advanced racing cars. The
ceramic material is also corrosion-
resistant and offers excellent
acoustic damping properties.
The carbon-composite discs work
in concert with a special brake-
pad compound, offering rapid
PCCB
deceleration and consistent
friction properties. The pads are
mounted in six-piston, monobloc,
aluminum fixed calipers at the
front, with four-piston units at
the rear.
The ultimate advantages of PCCB
are an extremely high braking
force that remains exceptionally
consistent under heavy use,
and a significant reduction in
unsprung mass, which improves
the chassis's responsiveness.
To distinguish Porsche Ceramic
Composite Brakes at a glance,
the calipers are painted yellow.
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The 911 Turbo I Safety