Bilstein measures its valve sensitivity in Newtons at a rate of 0.52 m/s (which is approximately 20 inches/second). One Newton is the amount of force required to accelerate 1 kilogram of mass to a rate of 1 meter per second squared.
Bilstein valve ratings involve two numbers — the Rebound Force and the Compression Force — written as XXX/XXX.
These numbers are an abbreviation representing 1/10 of the Newtons for that shock. For example, a valve rating of 275/78 means 2750 Newtons rebound and 780 Newtons compression. Higher numbers have firmer damping forces than lower numbers, thus a shock rated at 255/70 will be stiffer than one rated at 175/60.
For valving recommendations please read the Bilstein valving guide.
How many shocks should you put on your vehicle?
The role of a shock absorber is to transform mechanical energy (suspension movement) into kinetic energy (heat). If a shock absorber builds up too much heat, then it won’t function properly. Shock absorbers that are exposed to too much heat will fade (soften) and if the heat prevails, the shock will fail. If you’re experiencing excessive shock failure or fading, then it may be time to add a second shock. The addition of another shock allows the work load to be shared among both units. This provides many benefits, the most important of which are decreased friction and increased cooling capacity. The decreased friction occurs because lighter valved shocks can be used in a multi-shock setup. The lighter valve generates less friction and thus, less heat. The multi-shock setup also allows for greater oil capacity. Larger volumes of oil take longer to heat up.
If a multi-shock setup is not feasible for your application, then the easiest way of adding oil capacity is to install a 5160 remote reservoir shock.