I don't have the info handy right now but I remember using the chart from Speedway and found them all to harsh. The original rating and the next one "lighter".. all to hard for my taste. I ended up working with AFCO and have been pretty happy with it. But I don't remember the ratings off the top of my head! We nailed the fronts perfect and the backs are just a tad tougher than I'd like, but not bad... After I got that part done, AFCO was bought by Speedway and they came out with a line of Hot Rod shocks, double adjustable too.