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      11-01-2011, 11:09 AM   #52
luckyu
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Drives: 2007 328i, 1998 328i
Join Date: Jan 2007
Location: San Francisco Bay Area, California

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Quote:
Originally Posted by GaryS View Post
What is your source for the spring rates? The figures I've seen do not agree with your theory about tripling the front rate.
I think CVC is using tripling as an approximation, to avoid having to calculate wheel rates. :-) After all, as long as one is focusing on one particular car, you can make comparisons by comparing spring rates, without having to go to wheel rates. Makes sense.

It is true there are differences between the M and non-M cars in the rear, and the performance setup uses a stiffer front than BMW's ZSP setups.

But all the cars you showed have wheel rates that are very close front to back. CVC is talking about various coilover setups that have significantly higher wheel rates in front. What are they up to?

Like the Ohlins DFV setup, for example. Their standard springs give 110 pounds per inch wheel rate in back? What led them to choose such a low rate relative to the front, and how do they overcome the disadvantages? My theory about the mechanical limit in back does not explain their choice.
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2007 328i ZSP. M3 suspension: custom valved Bilstein shocks, Hyperco race springs, M3 lower control arms front and rear, M3 sway bars, and M3 subframe bushings. E46 front guide supports. Euro tail lights.
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