rear springs part 3

Choosing spring rate will control how how much travel is available in droop before the spring is unweighted.  It will also be related to how easily the car bottoms out.  Especially since inclined springs mean that I have a falling rate suspension.  The shocks that I have give three numbers, fully compressed length, fully extended length, and ride height.
For my shocks ALN5855P we have:

Extended height: 16.375 inches
Compressed height: 11.125 inches
ride height: 13.5 - 14 inches

Since coil overs are adjustable, I can moved the collars up or down to put the shock length in the ride height range regardless of the spring rate I choose.  However, suppose I choose a spring that is way too stiff. So that the spring only compresses .5 inches when I put the car onto its wheels.  If I put the ride height where recommended (14 inches), then we run out of load on the wheel at 14.5 inches extension.

Ideally, I want the wheels to become unweighted at full extension of the shock.  I previously measured the unsprung weight of the car at a surprising 330lbf or (165lbf per side) so a spring that sags 2.375 inches from 165 lbf would be 70 lbf /inch.  Since I have a 14° installation angle that becomes about 80 lbf / in.

That seems really low.  I have concerns that changing fuel load or passengers will significantly change ride height, and that the heavy axle when moving upwards in bump will be too likely to reach the bump stops in street driving.  I bumped the rate up to 150 lbf / inch.  Interesting to note that if you buy the cheap summit springs, you can see that it has QA1's logo faintly through the finish...

I finished the mount and put the springs and shocks in.  Here is a shot from the back.  I think this flies under the radar nicely.

I got in the trunk and jumped up and down.  The suspension moved freely about the same magnitude as any passenger car would.  Encouraging.  A few things were rubbing / not lined up how I wanted, so I will take a couple days to adjust some things, remove and paint all the rear suspension bits and attach them permanently.