Besides the entire brake system you'll also need S4 aluminum uprights, axles off a FWD since the S4's are 108mm and the Quattro's are 100mm, also flanges, wheel bearings and might as well replace your upper CA's if you haven't done so. PM Doc since he also did the swap. I have a set of used S4's all around but I've been too lazy to get to piecing together the set up. But with Hawk pads and slotted & dimpled rotors from SPP they make a badass brake upgrade.

Stock A4-->A8's-->S4-->993tt-->Stoptech, APRacing or Alcons if ya ballin

 

In my sig you can see the A8 kit (I spec'ced drilled/slotted rotors, and I'm also using Hawk ceramic pads) inside the 18" wheel. Also, click my screenname to get to my profile, and hit my photo album from there - there are a few other pics in there. It's a fantastic kit - the dramatic difference in stopping power is easily worth more than the price of the kit. You will NOT regret buying it.

 

Hey IMTHEDEVIL,

Where did you buy your brake kit?

 

I got it at www.ecstuning.com - very happy with it and ECS