Rear Spring Free Length for 100# Weltmeister Springs, How much do they collapse in length with time? How do you know if the Options

[jjs3rd914]

Our stock 1972 914/4 has 100# Weltmeister springs on the rear that are at least 15 years old (but with very few miles) that a PO installed new. I recently took them off to measure their free length which was 14.5". A supplier of the springs measured new ones at 15.0".

I recently had a post about the excessive rear camber on the car, both wheels at 2 deg. negative. Most of the advice were the rear springs were weak causing the sagging, even with a stack of shims in place.

So the question is, is a mere 1/2" of relaxing of the length enough to contribute to the large camber, or do I have something else going on? Has the spring's resistance (spring constant?) weakened? Is the free length even an indicator of weak springs?

Thanks,

jjs3rd914