Motion Ratio Calculator
For strut based suspension, D1 and D2 are always the same.  The angle is your steering axis inclination (SAI), the angle between your lower ball joint and upper strut mount.
For wishbone suspensions, D1 and D2 are usually different, but the angle is near zero.
For multilink suspensions, often the shock and spring are mounted in different locations, meaning your motion ratio for the spring and shock are different from one another.
Distance to mounting point (D1): 14 in
Total length (D2): 14 in
Angle of spring or shock: 75 degrees
Motion Ratio: 0.966 by Steve Edwards