Can anyone please explain the purpose of them, advantage and disadvantage?

 

purpose/pros: helps clear bbk, makes wheel flush to the fender
cons: may cause wheel vibration, possibly increased stress on the suspension

 

Looks & Clearance...

Sometimes you get wheels, which look great and suit your car, however don't fit to your liking as to backspacing (the width, where your car is situated in the wheel well of your car). In order to bring the wheel out more wheel spacers are used.

Secondary use is when you have brake kits, or special rims, that just barely do not clear your brake calipers. In this case the spacer is used in order to provide more clearance for the caliper.

Be careful when installing wide spacers... you may have to change your lug nuts to add length to them... this is a safety precaution in order for the thread to have enough "hold" in the hub.

 

Thanks for the insight. I like the sounds of it and what it will offer in terms of look but not really sold completely cause of wheel vibration and possibly increased stress on the suspension.

Anyone done it?
Any problems?

 

No problems with mine over 2 years of running them. Make sure you get hubcentric spacers AND longer bolts. Here's a couple of pics of my B6 with 8mm on the front and 15's on the rear:

 

I like it!

I see that your sig says "B7 S4 Avant", stupid question: I bought my mine in Dec. and its a 2007/2008 A4 avant. is it a B7 platform or B8?

 

Thanks. Yours is a B7 as the B8's aren't out yet.

 

is that an aftermarket FMIC I see peaking through?

 

Yup, an essential supporting mod for the BT

 

naturally... it increases gas mileage...