Could very well be Pinecone. But even with good springs I've seen the spring rates "change" over time due to usage/wear with everything else being equal using scales and sping testers. Might not be such an issue for the street, but there have been times we've chased the setup to find that a spring has lost/changed its rating. As I mentioned, for those who might be concerned with it, it was just a thought for consideration.
S. Maykowski, Columbus MS.
My '99 Z3 Alpine White 2.8L Speed Buggy