Probably I could give you a hand regrading spring chart.
Petit RC Universal Spring Chart
RCinGreece - Spring Rates Chart
Thard.co.uk - Universal spring sheet
NitroRC - Spring Table (Associated, Corally, HPI, Losi, Mugen, Schumacher, Yokomo)
Team Associated - Spring Rate Chart
RC Racing USA - Team Associated Spring Chart
Team Losi - Spring Chart
The source is the following
one
Ok, now just hopa you were looking for those kind of information - otherwise I will feel like a idiot.
For Yokomo Spring Chart, have a look on one on the three first links. The first one (petitrc) might not work, don't seems to work tonight.
Hope that can help more than one!
PS; Jimmy, if I got wrong here, please, delete the post!