i am waiting to do this, i was going to go with poly and aluminum control arms for the m3, they are supposed to be bolt in place of the steel ones and are fairly cheap ($175/each). they say that by using the m3 bushings that you will have increased stability at higher speed than with the stock ones. i was going to use poly because i am not going to do the job again later (do it right the first time), plus the rigidness of the poly will help with handling. the only thing is i was also wondering if the increased caster will adversly affect my car being lowered 2.5 inches, i think that it would help out but i dont specialize in suspensions.
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