softer ride

SINISTER

Why is the rear spring rates stiffer on our cars?
Nismo Spring Rates:
F - 8.6kgf/mm (480lbs/inch)
R - 9.3kgf/mm (520lbs/inch)

Then when looking at coilover options like powertrix the spring rates flip?
Using swifts F-12 R-11

I suppose it has to do with the OEM damper valving...but seems like I read long ago that most rear wheel drive cars would/should have stiffer spring rates in the front.
I suppose our cars ride is maybe a clue. With fairly low spring rates in general in the front and rear... the harshness of the ride must be in the way the engineers tuned the valving in the dampers? ...so perhaps this is why the spring rates are stiffer in the rear and less in the front on our cars. However, when you switch to coilovers the valving is more "normal" and spring rates then switch back to a more agreed upon normal of stiffer in front and less stiff on the rear?

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