Ground Control rear spring crooked

[Pattquin]

Hi guys,

I have been running ground control rear coilover system on my 88 e30 with Bilstein shocks.
The spring are 440 lbs/inch, 2.5 I.D. and 6 inches long.

The problem is that after a couple of miles driving the car, the spring gets misaligned and does not sit well on the lower perch.
I tried to contact Donovan at Ground Control but no answer....

Did you guy experience the same problem? Should I try something else?
Do you have any recommendations?
Any suggestions would be appreciated.
Thank you

See first picture is with the compressed suspension (not lifted).
Second picture is the side view, on 16 inch wheels, normal ride height.

[ehrawn]

It looks like the spring is too short for suspension geometry. Found this other thread which prescribed the tall rear shock mounts as a fix. https://www.r3vlimited.com/board/for...with-bilsteins

[mtech325]

Out of curiosity, what rate are you using for the front? I ask because 440lb is often the front spring rate GC usually uses, while the rear springs are typically barrel shaped for the rear when below the 600lb rate, so maybe the front and rear springs have been switched by accident?

For one of my cars, I am using a linear 500 lb. 6-inch x 2.5-inch diameter spring in the rear and it sits normally on its perch once the suspension is loaded, and with the normal rear shock mount as well. However, another mistake i've made in the past is using a 2.25-inch diameter spring (another common GC rear coilover size), but accidently kept the 2.5-inch diameter spring perch on the threaded collar, which didn't allow the rear spring to properly sit flat on the perch.

[Pattquin]

I use 375 lbf front spring 6 inches also.
i did not check if the perch was designed for the 2.5 inch spring but I guess it is since it came in the same box from GC. I did not know Ground Control have barell shape springs, unfortunately they dont answer my questions....but thanks for your help