There was just a long thread on spring rates and spring sources on the
Europa group. You might download and search the knowledgebase at:
http://www.lotus-europa.com/knowledgebase.htmlor just ask again on that group. There are several autocrossers active
there who can help you to the right F/R spring rates to suit your
purposes. The calculations seem to live in their heads!
I concluded that there are many sources of custom springs out there,
but that you want a reputable vendor to make yours due to the many
variables that can mess up a spring. The cost for a quality spring
would probably be comparable to or less than DB, who is just acting as
a middleman in this transaction.
Doug Nicholls, 54/1822 Ma~