Thread: 22/28 vs. 22/30
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burgermeister burgermeister is offline
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Join Date: May 2007
Location: Springfield
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Quote:
Originally Posted by Noel View Post
One thing that wasn't mentioned was the notion of loosing weight, especially at the back of the car and the affect this will have on the relative spring rates. Does anyone know any correlation for this. For example, loosing X number of pounds equals Xmm of torsion bar. Or is such a correlation not accurate?
An approximation of your rear ride frequency is sqrt(2*k/m) / 6.28 Hz (did I remember that right?), k being the wheel rate for one side, and m being the rear axle weight divided by "g" (you want mass, not weight). Your unpsrung frequency is probably dominated by the tire rate, so torsion bar size doesn't matter much for it.

So, keeping 2*k/m constant will keep your ride frequency the same. So, for a 10% mass reduction and 28mm bars, 27.3mm bars would be similar ...

Or so I remember from classes take long long ago in a galaxy far far away ...
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Old 12-14-2007, 12:54 PM
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