The 170 is for those that are concerned about too stiff a ride, or maybe they’re still running the original tank, no bed floor, that kind of thing. It’s just a softer ride is all.
The 200 is the best all-around spring rate. Good on the street, still can do some “truck type stuff”, good performance, which is most ideal for the common fuel tank swap to behind the axle.
The 250 is for the autocross or with a handling/performance as the priority. This level is going to be where a person is willing to sacrifice some interstate comfort for better handling around the twists and turns.
Shock part numbers are going to be specific to these kits as they use a bushing in one eyelet and bearing in the other but other than that are the same as the Proma Star shocks.
DS511 for single adjustable kits. DD511 for double adjustable kits.
Springs are all 12” standard 2.5” ID springs just like the Proma Stars:
12HT170
12HT200
12HT250