Shock Absorber Sizing Calculator

Size shock absorbers based on sprung mass, spring rate, desired damping ratio, and suspension travel.

Input Parameters

Results

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Critical Damping
lbs·s/in
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Target Damping
lbs·s/in
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Rebound Damping
lbs·s/in
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Natural Frequency
Hz
Note: Damping ratios of 0.25-0.40 are typical for street cars. Track cars may use 0.5-0.7. Rebound damping is typically 2-3x compression damping.

Reference

Wheel Rate = Spring Rate x Motion Ratio² Critical Damping = 2 x sqrt(Wheel Rate x Mass) Target Damping = Critical x Damping Ratio Shock Damping = Target / Motion Ratio² Rebound ≈ 2.5 x Compression damping Natural Freq = sqrt(k/m) / (2 x pi)