hi DONT KNOW WHAT HAPPENED TO MY POST BUT HERE IT IS AGAIN.DOES ANYONE KNOW OF A WAY TO CHECK IF THE CAR SUSPENSION SPRINGS ARE MADE TO YOUR SPEC.mUST I MAKE A GADGET TO MEASURE THE SPRING RATE.i HAVE HAD 4 SPRINGS MADE HERE IN SOUTH AFRICA AND I AM SURE THE GUYS DID NOT DO IT PROPERLY AS THE CAR FEELS SOFTER ONCE I HAD FIT THEM tHE CAR IS A DATSUN 1800J SSS [STANZA IN AUS]

Without looking at the quality of the spring steel im pretty sure you can work it out roughly by measuring a few things like:
Spring height.
Coil diameter.
Coil spacing.
Coil thickness.

Theres probably a professional formula somewhere on the net though if you Google it like this:

http://www.pontiacracing.net/js_coil_spring_rate.htm

Thanks looked on google and man is it a valueble search engine!!!