jcmII

nothing earth-shattering to ponder, but here's my question: Will it make a noticable difference if I went from 18 x 8.5 BBS CH's to 18 x 7.5 Volks (the popular ones)? I think we're talking about 25-27 lbs. vs 16-18 lbs.

My car has H&R coilovers, and I'm not sure I like the ride anymore. I'm wondering if a much lighter wheel will make the car feel more......nimble? It feels clunky and harsh over small cracks and creases in the road (and the roads are pretty good where I live). Is this something I have to live with if I'm lowered with 18's, or will lighter wheels make a big differnce. Thanks ya'll

V8_SPANKER

this means that the wheel is easier to spin, therefor faster acceleration times.
will you be able to tell, I don't know, but you might.

Nogaro

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Nogaro

IMO, you need to either back off on the coilover or the wheel size.

Ray Khan

agreed

Avantgarde

but my non-technical consensus is that unsprung weight (i.e. rotational) on a 17" wheel is worth about 6.6x sprung weight. So if 100 lbs. = 10 hp then dropping 10lbs. x 6.6 = 66 sprung lbs equivalents = 6 - 7 hp.

* BUT *

You really need to account for where the weight reduction occurs, the closer to the hub the less benefit. A somewhat lighter tire is better than a really light wheel...

this has been discussed to death on both roadfly and bimmerforums - check out this thread

http://www.bimmerforums.com/forum/showthread.php?s=&amp;threadid=4023&amp;highlight= unsprung+weight

Levish

the nimbleness will be retained, the wheel will be even lighter and the ride will be less harsh

Nogaro

Wheels are getting lighter and lighter but tires are pretty much the same.

Sometimes the Alu of the wheel is lighter then the rubber it replaces when going to a 18".