From GTR2 Engineers Handbook
Fast Bump - Controls the rapid upward movement of this suspension corner following
bumps and curbs. This Bump is described as “Fast” because the damper is moving up
(compressing) in a rapid motion, usually above 100mm/sec (use telemetry). So this adjustment
controls how a tyre conforms to the road as it’s negotiating the leading edge-topeak
of a bump or road undulation. If you find the car pushing to the outside of the track
in a “skating” fashion over bumps, then soften (lower) this setting. If the car floats and
changes direction erratically, then stiffen (higher) this setting. When in doubt, go softer.
Slow Bump - Controls the mild UPWARD movement of this suspension corner caused
by a driver input (steering, braking, throttle). This Bump is described as “Slow” because
the damper is moving up (compressing) in a slow motion, usually below 70mm/sec
damper speed (use telemetry). Used to affect chassis balance while we are transitioning
into, and out, of the corners. Decreasing this number will speed up how quickly a corner
accepts weight transfer while we are transitioning. Increasing will slow it down.
Fast Rebound - Controls the rapid DOWNWARD movement of this suspension corner
following bumps and curbs. This Rebound is described as “Fast” because this damper is
moving down (extending) in a rapid motion, usually above 100mm/sec (use telemetry).
So this adjustment controls how a tyre conforms to the road as it’s negotiating the peakto-
trailing edge of a bump or road undulation. If the fast bump setting has been changed,
then it’s usually a good idea to change fast rebound in a similar manner.
Slow Rebound - Controls the mild DOWNWARD movement of this suspension corner
caused by a driver input (steering, braking, throttle). This Rebound is described as “Slow”
because the damper is moving down (extending) in a slow motion, usually below 70mm/
sec damper speed (use telemetry). Used to affect chassis balance while transitioning
into, and out, of the corners. Decreasing this number will speed up how quickly this
corner gives up - or “sheds” - weight transfer while we are transitioning. Increasing this
setting will slow it down.