Are there any other Audi models that have bigger brakes than the A6 Avant does? Seems like the braking prowess matches the acceleration of the 2.8 - not great. Granted I'm used to throwing around much lighter cars...

Maybe someone upgraded to aftermarket and their stock calipers/rotors are available?

They are bigger than your 2.8 fronts.

The C5 2.7T from '02-'04 dropped the HP2s, but I think they're still bigger than yours.

The B6 S4 has bigger brakes, as does the RS6.

Hey TJ, I've been looking into brakes for the Avant too. Here's the deal.

No one makes a brake upgrade that works truly like OEM. If you read over some of the documents <a href="http://stoptech.com/technical/">here</a>, you'll see that keeping the brake bias front to rear is very important to maintaining stopping distance.

Stoptech engineers brakes to keep the factory f/r bias. If you lose that, your ABS or traction control (not in our 99 avants) could be thrown off. Other companies sell upgrades for the 2.8, like porsche brakes, but they don't make an effort to keep them within those factory tolerances. That said, I'm sure they work great, it's just that I won't take chances with my safety.

Stoptech unfortunately does not make a BBK for our cars, the best that you can do is get a 'Stage 2' kit that includes slotted rotors, aggressive pads, and stainless lines. It will be an improvement, but not porsche brakes. Unfortunately, that's just the case with the 2.8.

I initially used Hawk HPS pads on stock rotors. They work pretty well, but I think that upgrading to stainless brake lines, especially on our 6 year old cars, would help a lot too. I even tracked 2 days on that setup. I'll probably eventually upgrade to slotted rotors and the ss lines when these go bad. I think the kit was about 700 bucks, with front rotors and pads, and stainless lines all around.

Best of luck and let me know how it goes.

Located in the wheels &amp; tires tech section of all places?!!?
<a href="http://www.audiworld.com/tech/wheel1.shtml">A8 Brakes for other Audi Applications</a>

They require a different upright.

The 99A6 brakes are much more like the A4 with the steel uprights. The carrier bolt holes are different, and thus won't fit the B5S4 brakes.

You can go to the 312mm size that comes with the new B6 3.0L A4's.
You just need the rotors and carriers.

That's what the "A8 upgrade" from my post above suggests.

the line between marketing and technical accuracy may not be maintained throughout the complete article. I'm not fond of their graph of the S4... it notes in itty bitty text... NO ABS OR ESP (or something to that effect) how many of the guys buying stoptech products for their S4's disable both esp and abs??? what bothers me even more is that they used this as a method to achieve a possibly desired result in a test that they then included in their technical section... which now feels way too much like marketing because they made an effort to not make the cars configuration completely known to the reader.

The footnote in that chart in their Brake Bias whitepaper says "Without EBD or ABS active". Probably most who upgrade their calipers track their car; and probably most who track their car, prefer to stay out of ABS (even if they don't pull the fuse). Without ABS, the wrong brake bias will result in increased stopping distances and possible instability. Even with ABS, a badly screwed up brake bias will increase stopping distances slightly.

I'm not sure if any Audi's have Electronic Brake Force Distribution (EBD), but the D2 A8/S8 does not.

<img src="http://www.stoptech.com/whitepapers/stoptech_balanced_chartweb.jpg">

We do all our tests on the same car the same day with the same tires. The Chart in question has a footnote regarding rear bias only that says if ABS is disabled then the platform is unstable.

The Stopping tests were done with ABS enabled.
We do have a suite of tests that includes an ABS disabled test to insure we have front bias. We also check heading angle in our J-turn tests to compare F/R bias versus stock.

The distances get worse on any platform as you increase front brake torque past the stock torque (keeping tires and surface mu the same).

Some platforms e.g. 3/4 ton trucks punish you severely if you fall off the stored PV curve.

We are the only after market brake company that bothers to do this extensive testing. We could just as easily make 40-44 calipers as 36-40. The S4 stops better with 36-40 front pistons sizes versus the 40-44. If you put on more aggressive friction and keep the tires constant you will increase stopping distance. We measured a 5 foot increase in a M5 going from stock to Pagid blue at 80-0. Is anyone else trying to explain these issues?

If you do your homework you find we have our science correct. We do not bend the laws of physics to suit our purposes.

Bob Lee
StopTech LLC

I'm just turned off by itty bitty little asteriks with important info attached as if it were meant to be overlooked. That is the sort of thing I expect from somebody that has some thing important to hide. I've never said anything bad about your products, however I dont trust technical information in article form published by mfgs, thats just how I am.

that the note "without EBD or ABS active" applied to the entire chart, not just the "Platform Unstable" section.

BTW: I had said "Even with ABS, a badly screwed up brake bias will increase stopping distances slightly." You measured a 5 foot increase in a M5 going from stock to Pagid blue (I assume front only) at 80-0. Going from a stock probably 0.35 cf pad to the 0.48 cf of the Pagid Blue is a huge shift in brake bias. Only a 5 ft increase in stopping distance is a credit to ABS, and I can imagine it'd be a huge increase without ABS.

There are never enough footnotes to satisfy the the technical reviewers. Until we raised the bias and balance issues, some people assumed certain manufacturers sprinkled Brake Pixie dust on their kits to make everything work. As the IBM ad states there is no brake pixie dust.
Hopefully we can engage you in the future with more technical data. I have three new non partisan articles planned for our technical section.