B6 A4 Budget brake upgrade for HPDEs/Auto-x

[wazzu70]

Hello, I tried searching this but I did not find much useful information that is well compiled.

I took my A4 avant to an autocross school today to get some seat time in it since the car is pretty new to me (4months or so). The car did pretty well for a daily driver with Bilstien sports and H&R sports but the one place it lacked was braking, in a BIG way.

At the end of the day on my last run I had the front pads literally pouring smoke out from them This is not cool and it makes me concerned for my safety if I really need to get on the brakes for an emergency.

I have no idea what pads are in there now since I just got the car, but I assume its some low grade Autozone pad or something.

I am not looking for someone to tell me to go drop tons of money on some ridiculous brake package to fill in my wheels, and I am hoping this motorsports&racing forum can provide better advice than that based on experience. I have been around racing e30 BMWs for about 5 years and even in our 12 hour endurance car we just run stock calipers, an upgraded pad (special blend made to last through an endurance event), Motul fluid, and brake ducts. No ridiculously expensive hardware needed.

I am curious if a similar setup on my A4 will yield the results I am looking for? I am also aware of the B5S4 caliper upgrade but I am unsure if this really offers much benefit. Also do I need to increase my rotor size with this? What about the rear calipers...will I be overpowering those with bigger fronts? any tried and true true performance upgrades out there?

If the B5 calipers are the best setup, are they available on any other vehicle? I have seen mixed information about other cars having the same calipers but part numbers do not show that to be true.

This is my daily driver, but the complete lack of bite to the pads concerns me even for this duty. While I am in there I might as well get a decent setup going, right? Since this is my DD and I have a track duty car I do not need to go all out, so please keep affordability in mind. This will not be used in a highly competitive car, just for fun runs, but I still would like to get some decent bite.

Thanks for the help

[dchan189]

I'm right there with you. But you wouldn't necessarily need to upgrade calipers. I would just get:

Pads, Hawk HPS or HP+ if you are more autocross oriented. Good for DD too.
Rotors, something slotted and can disperse heat.
Fluid and Brake Lines for more pedal feel.

I think all this will make your car stop better

[wazzu70]

Glad someone knows where I am coming from! My personal preference on pads is Porterfield and this car will get the street compound, but all in all its the same. HPS are really good too!

Do you have this setup on your car with the stock calipers/discs? I think it will definitely be a huge improvement, but if the S4 fronts are a lot better it might be worth it to upgrade. Then again I can always just use the factory stuff with real pads/lines/fluid and see how that does before upgrading. I might be pleasantly surprised and my wallet will thank me!

[wazzu70]

I did some testing of my brake system on the way to work today as I was kind of concerned about the lack of performance from medium speed. Since freeway speeds are faster than I was going on the course, I wanted to make sure I could adequately have brakes at those speeds in case of an emergency. I found that most of the time my brakes grabbed fine, but every once in a while the pedal would be very stiff and the brakes pretty much non-existent. I will test my check valve that goes to the booster and make sure it is functioning properly. If it is not, well, that could be a huge source of my problem obviously. The few times my brakes were just not there were after acceleration so it is highly possible the booster is becoming pressurized (turbo car). It did not happen all the time, but that means the valve may be sticking and not completely failed.

[wazzu70]

Well I managed to get some rotors/calipers from a 3.0L V6 A4 someone was parting out locally. This will give me the same calipers as my current car, but will allow for a rotor that is about 1" larger in diameter. Since I got such a deal on the parts, I figured...why not? I am just going to resurface these rotors and my rears and upgrade the pads to Hawk HPS all around. Also adding stainless lines and some fluid with a higher boiling point to see how that works.

If I am not satisfied with that setup THEN I will consider spending some more money. I think this should be plenty sufficient though as pads and fluid are usually big hold backs on OE systems.