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Old 17th October 2011, 10:04 PM
Tilly819 Tilly819 is offline
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Join Date: Oct 2008
Location: Leicestershire
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also remember that the spring rate change with respect to the sin of the angle

example:

front spring rate is 350lbs/in IIRC @45 deg
if the spring were vertical it would need to be (350xsin45 = 247.5lbs/in)

to find the new spring rate we can take the vertical rate and apply a new angle of 60deg (measured from horizontal, dont use 30 you have to measure up from horizontal not down from vertical)

247.5 / sin60 = 285.7lbs/in

this is inly the case if the outboard pivot point stays in the same place and you move the inboard pivot point.

if you move the outboard pivot closer to the chassis then the leverage effect it has on the shock with be much greater and thus require a heaver spring rate and will also make it more lightly that you will bend or worse snap a wishbone.

example if the outboard pivot for the shock is 400mm away from the chassis pivot for the wishbone it is connected to and it supports 100KG if you half this distance you double the load. so now at 200mm it has a 200KG load and so on... this is very bad practice

making the shock more vertical is a very good thing and can be done by moving the inboard end of the shock. the outboard end of the sock should be as far outboard as possible so as to reduce the bending moment on the wishbone. wishbones are not designed to take bending loads, they are designed to take load in tension and compression.


hope this is of some help

tilly
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Last edited by Tilly819 : 17th October 2011 at 10:12 PM.
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