Originally posted by m42technic
The front is about 18% stiffer and the rears is about 33% then the 'iS' springs.
Who know how much stiffer they are compared to the shitty 318 springs.

Like 80%. lol
Just kidding, Just kindding.
Information taken from:
I have M3 springs btw and it's VERY noticable.
Allot less roll :o
My blown shocks are also more noticable too. :( *bounce *bounce
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