Spring Rate Wheel Rate Calculator
Convert spring rate and motion ratio into wheel rate for setup comparisons.
Calculator guide
Converting spring rate to wheel rate
This calculator estimates the effective spring rate at the wheel and compares corner load with that rate.
Inputs and calculation
- Spring rate, suspension motion ratio, spring angle from vertical, and corner weight.
Wheel rate = spring rate × motion ratio² × cos²(spring angle).
The displayed load-to-rate deflection is corner load ÷ wheel rate; metric corner mass is first converted to newtons.
How to interpret the result
- Wheel rate is more useful than spring rate alone when comparing suspensions with different motion ratios. The load-to-rate value is a simple static comparison, not full suspension travel.
Assumptions and limits
- Motion ratio must use the same convention as the formula: spring travel divided by wheel travel.
- The estimate excludes anti-roll bars, bump stops, tire stiffness, installation compliance, rising-rate geometry, and aerodynamic load.
Example: inboard spring effect
A 500 lb/in spring at a 0.90 motion ratio and zero spring angle produces about 405 lb/in at the wheel. A 700 lb corner load divided by that rate is about 1.73 inches.
Compare spring changes with the full setup
TuneWorks keeps suspension changes connected to the car, setup, session, and notes.