Thread: HD Spring, same damper as before - what effect?

Depends on the springs involved and the dampers, but in my experience a stronger spring will speed up the frequency /speed of the movement of the spring and the ride will feel stiffer, as the body will move quicker in relation to a bump and the spring will deflect less as a stiffer spring will take a greater force to move it a set distance.

Springs are usually rated in lbs per inch of deflection, and for example a standard RRC front spring is rated at 133lbs per inch so it takes 133lbs of force to deflect the spring one inch. The most common aftermarket spring is 160lbs per inch so for 133Lbs force it will only deflect say 0.9 inch.
That is why Range Rover Classics have very light springs and the load leveller, to reduce the frequency of the movement of the body after hitting a bump.

Lght springs enable the use of lightly valved shocks the job of which are to control the deflection and rebound of the spring. However seeing the Land Rover axles are so heavy, the shock in a Land rover can control a significantly heavier spring as the force it exerts is a smaller percentage of the unsprung weight than in an independent car. Shocks are only really to control the rebound of a coil spring and if they do that without a secondary "bounce" they are stiff enough.

A stiffly valved shock on a soft spring will do a similar thing in that it will reduce the amplitude of spring movement when hitting a bump and the car will feel "choppy" . Even a lightly valved Bilstein will make the ride of an RRC "choppier" as the design provides a higher level of compression damping than the OEM shocks.
Look this is very simplistic and there are heaps of other factors at play, such as low speed damping vs high speed, compression vs rebound damping etc etc.
Suffice to say if you put a stiff shock on a standard Land Rover suspension you will ruin the ride. The ride will not get much worse if you then add stiffer springs but the abilitity to flex on uneven roads "articulation" will suffer more.
Regard sPhilip A