Suspension Tuning

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While tuning is usually a very daunting aspect, its usually very straight forward. Unless you have had a lot of time with this particular car set-up and are thus incredibly familiar with how it behaves, I suggest avoiding fiddling with any of the suspension geometry. Instead, pick a nice neutral set-up (minimal toe, camber, etc) and optimize the spring and damping rates for that setup.

To do that:

  1. Start with all spring rates at highest setting, rebound damping at middle setting, anti-roll bar decoupled
  2. Decrease spring rate until all shocks start to bottom out once per lap. (This can be check by placing zip-ties on the shaft of the shock and noting their resting place after a lap.)
  3. Couple Anti-roll bar at highest setting
  4. Make note of coupling point that allows for fastest lap time on tracks with hair-pins and slaloms of varying tightness
    1. Use a binary search algorithm: start with highest, then the lowest (if high is not high enough or low not low enough, switch in new bar), then half way, then half way of the preferred side, and so on
    2. To tell the preferred side, ask the driver whether the middle rate was too much like the highest or the lowest rate and then go the opposite direction
  5. Finally, use a binary search to find desired rebound damping setting

The order is based on which factors will most confound the remaining factors (i.e. Spring rate plays a big part in cornering and how things need to rebound, but rebound rate and anti-roll rate play little role in absorbing impacts from jumps or obstacles) and the setting starting point is based on by starting closest to the theoretical optimum. (i.e. Stiffer springs means more normal force, means more traction, etc)