I have a 1998 Audi a4 avant quattro and am interested in a brake upgrade. I already got some aftermarket parts for the front, but I have some questions about the rear. I may be able to get a pair of rear s4 calipers and then use the s4 vented rotors. Basically I want to know if the rear s4 brake setup will mess the front rear balence of the car when braking. The front rotors are stock size. I know people have done the full s4 swap, but I am just looking at the rear. I want a more balenced look. Thanks.

 

An S4 swap will get you vented rotors in the rear, but the added weight and cash isn't worth it. You wont notice much of an improvement. It shouldn't offset the balance if you swap to S4 OEM parts. I believe the master cylinders and bias valves are the same.

 

the front brakes do about 70-80% of braking anyway, so it's not going to mess any bias up, the S4 upgrade really dosen't improve stoping distance so much as it does brake fade like the A8 rotor upgrade does and rotor warpage because they're vented discs, the rotors themselves are really only 20mm bigger I believe. if you want to acutaly improve stoping distance, 034 has B7 S4 brake upgrade options, they use 300mm rotors and also different calipers i believe which offer drastic improvements. The S4 and A4 uses the same master cylinders like tweaked said so no change is needed.

 

I did my own S4 upgrade before 034 offered it and I cannot say that I notices a big difference because I also did the fronts as well.

034 makes it easier since they offer a kit, but most of your braking is done in the front and the cost is not justified by the slight improvement. I got a good deal from a friend who was parting out his B6 so this would not have been considered otherwise.

Here are a few pics if you are interested and can source the parts cheaply.

Here are the parts:




Custom milled spacers I had made:


















What they replaced:




Just for comparison, this is what went on the front:

 

Thanks guys, I appreciate the help. BTW thats a pretty sick setup fred2ka4, althought slightly out of my price range. Now that you have the front and rears done, is there a noticeable change in stopping distance, or just less brake fade?

 

I did notice a difference in both stopping distance and brake fade, but it was slight. Is it enough of a difference to justify the cost ...... No. If you want a good setup at a low cost I would recommend ss lines all around and upgraded pads.

I already had a stage 2 version 1 setup from ECS Tuning and upgraded to a stage 2 version 2 and then added 911 calipers and custom brackets. At the same time I did the S4 rears but I did not notice any difference in the front to rear bias. The car stops on a dime and the brake feel is excellent.

 

Fred2ka4: your setup looks sick.

zabranca: The stock brakes with a good set of pads are proven at the track and AutoX. Best bang-for-your-buck is A8/TT front upgrade and a set of Hawk pads and SS lines. Replace the brake fluid while you're at it.

If you have the dough for big brakes and wheels, go with something that looks as good as Fred's. If not, go practical with A8/TT.

 

Thanks for comment and thanks for reminding me of something I forgot to mention. I got the wheels first, and they were designed by IForged as the S4 BBK setup, which will allow for a stage IV. The person I bought the brakes and wheels from was running Porsche Cayenne 6 calipers in the front and they fit perfect. I had purchased these only to find out that I would have to swap out the spindles and CV axles, and I didn't feel like going through that hassle.

Your wheels have to be taken into consideration when upgrading the brakes, but if you go with factory parts you should be ok but you still want to verify offset, and clearances.

Here is what I almost had on the front:

 

ebay vendor ucautoparts.
Cross drilled fronts and backs to fit stock 96 b5 A4 200$ shipped.

Not affiliated other than a satisified customer.
Been running them two years now.
Your mileage may vary, but now you know.

 

Hello to everybody,
I'm also interested in a brake upgrade,but not so cute.I have a 1996 Audi a4 avant .In my car rear break supports-cylinders are old type and made from a rust iron and I would like to mount the newest supports made from aluminum. Is it possible? What differences between them? Vissualy I see only one difference in the hoses of brake cylinders,but I can change them also. I want to do this not for tuning or some one else,but I have problem with a one rear brake cylinder and it's difficult to get a second hand cylinder of old type.
Thanks.