Yesterday I decided to take my 18 inch Sport Edition Teknos off for the winter and replaced them with my factory 15s....I was amazed with how much faster my car is with the stockers! There is a definate noticible difference in my 325ic's acceleration, cornering, and breaking. I know that everybody says that the less unsprung weight the better, but I had no idea that it had this much of an impact. I hate the look of the stockers and love my 18s.... but now I don't even want take the 15s back off!!! By the way, I weighed my 18 inch rims with tires and they came to roughly 58 lbs per wheel....I know this is pretty high but does anybody know what the factory rims/tire weight in at? Should I look into a lighter pair of larger diameter rims????

yowza! Go with some SSR Competitions, in 17" they're about 16.5-17.5lbs a peice, then add 20lbs for tires and you're at ~37lbs a corner vs 58lbs a corner, 20lbs a corner! thats a HUGE savings!

The mfg's lit for your Teknos put them at 23# each. 35# for tires (58# total) sounds like a bit too much so maybe the lit is misleading.

Your stockers should be in the 18 - 20# range, depending on the model.

SSR and many others do make 17 and 18" wheels under 20#. Look here...

http://www.europeanspeed.com/wheelweights.htm
http://www.wheelweights.net/
http://www.wheelspecs.com/main/index.php

Quick note: all three of these websites have quite a bit of overlapping info, but they all have a few entries that the others do not.

Unsprung weight is a handling issue. The rotational mass affects acceleration. Although wheels are common to both, they are not the same thing.

If you noticed a difference and care, I would definately look into lighter wheels. 17" wheels look great on E36s and definately save a few pounds per wheel. I think that most people here would agree that 17" wheels actually handle a little better as well (18's for show, 17's for go).

Yeah wheel/tire weight makes a HUGE difference in acceleration and braking. A typical 15" E36 wheel/tire package weighs in at about 36-37lbs. 15lbs for the 15x7 wheel and 22lbs for the tire.

I even noticed a difference when I sold my 16.5lb BBS RK's with 20lb Pilot Sports, when I went back to stock. Even though there is only a few lbs of weight difference, the sheer size of 18's make them more difficult to get moving.

I had a 55lb 18" wheel/tire package and it RUINED the feel of my car. People with heavy 18's/19's make me laugh...what a waste of money to make the car perform worse.

BTW.....those Sprot Tekno's (about the bottom rung in quality) have to weigh a LOT more than 23lbs as the average tire weighs in at about 25lbs....that wheel weighs more like 33lbs!