Porsche 911 GT3 R Technical Manual page 79

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 5.7`. The ratio of the front spring is
0.73. The thread pitch of the spring saddle is 1.5.
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