Porsche 911 GT3R 2010 Technical Manual page 61

6.1.2. Front dampers
6.1.2.1. Rebound
6.1.2.2. Bump
Changing the spring rate (spring stiffness) directly affects the vehicle ride
height as well as the toe. The ride height must be adjusted by four
revolutions to compensate for one step in spring rate change. For
example, when the spring rate is softened by one step the ride height
must be lowered four turns to compensate. If the spring rate is stiffened
the ride height must be raised by four turns. Changing the ride height
about 10 mm changes the toe about 2.4'. The ratio of the front spring is
0.7. The thread pitch of the spring saddle is 1.5.
A 2-way damper adjustable in bump and rebound (compression / droop) is
fitted to the front axle. The bump and rebound damping forces are
adjustable in the high-speed piston range. Both softer and harder are
adjusted on the valve block.
The rebound is adjustable in the high speed range. The high-speed
adjustment range has 16 positions (1 = less damping forces, 16 = higher
damping forces).
The bump is adjustable in the high speed range. The high-speed
adjustment range has 16 positions (1 = less damping forces, 16 = higher
damping forces).
Attention:
When changing the existing dampers for those of another
manufacturer, it is necessary to ensure that the recommended
ride height and spring travel values are retained. Porsche AG does
not accept any liability for any subsequent damage to the
suspension or related components.
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