choosing spring rates

[iluv2moan]

if u dont have an unlimited budget for trial and error, how would u go about choosing a set of springs with specific spring rate for a given vehicle for time trial/circuit racing.

is their any rule of thumb based off corner weights etc

[mitchy]

best of getting opinions from people with the same car

whilst weight affects it, as does where the spring/strut sits in reference to the control arms.. a spring that is closer to the pivot point (where the arm attaches to the chassis) need's to be "harder" than a spring that sits closer to the wheel... (force x distance or some shit)

so you could have 2 cars, that for arguements sake have 500kg at each corner, yet one runs 10/8, and the other runs 5/4 due to where the spring attaches, to achieve the same effective spring rate.

[iluv2moan]

yeah - understand theres going to be many influencing factors, but not many people race mk3 supras :)

spoke to one racer with same chassis (soarer) and he said that wheel rates are far more important then spring rates. not sure what this means sinc ei havent googled much into it, but he said calcs can only go so far - trial and error is where its at :(

[iluv2moan]

thought i better google myself first haha

http://autospeed.com.au/cms/title_Spring-and-Wheel-Rates/A_2904/article.html

[iluv2moan]

answered my own question pretty much - helpful info if anyone else is/was to lazy to google