Go Back  AudiWorld Forums > Audi Models > Audi A8 / S8 > A8 / S8 (D2 Platform) Discussion
Reload this Page >

Why do you think a brake pedal gets soft after repeated hard braking?

A8 / S8 (D2 Platform) Discussion Discussion forum for the D2 Audi A8 and S8 produced from 1994-2002

Why do you think a brake pedal gets soft after repeated hard braking?

 
Old 09-27-2003, 07:49 AM
  #21  
Elder Member
 
Join Date: Mar 2001
Posts: 11,968
Likes: 0
Received 0 Likes on 0 Posts
Default This would also allow more heat transfer ...

from the wheel to the hub and wheel bearing. The front wheel bearing probably already runs hot enough.
ryoung is offline  
Old 09-27-2003, 08:06 AM
  #22  
Elder Member
 
Join Date: Mar 2001
Posts: 11,968
Likes: 0
Received 0 Likes on 0 Posts
Default You weren't the only car with hot brakes at Road America :-)

<ul><li><a href="https://forums.audiworld.com/s4/msgs/1406013.phtml">S4 x-post</a></li></ul>
ryoung is offline  
Old 09-27-2003, 09:05 AM
  #23  
AudiWorld Super User
 
Join Date: Apr 2003
Posts: 2,300
Likes: 0
Received 0 Likes on 0 Posts
Default ah of course; on a 2-piece racing rotor, the hat and disk are MUCH more isolated, thermally.

<center><img src="http://www.ultimategarage.com/MovFront2.jpg"></center><p>
Jkay is offline  
Old 09-27-2003, 09:20 AM
  #24  
Elder Member
 
Join Date: Mar 2001
Posts: 11,968
Likes: 0
Received 0 Likes on 0 Posts
Default Stasis machines cooling vanes into their aluminum hats (big picture warning) ...

Unfortunately, I'm only using their hats in the rear.

<img src="http://www.stasisengineering.com/images/Brake_TS_Sub_2.jpg">
ryoung is offline  
Old 09-27-2003, 09:47 PM
  #25  
AudiWorld Super User
 
s4master1's Avatar
 
Join Date: May 2003
Posts: 2,728
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Why do you think a brake pedal gets soft after repeated hard braking?

to all of you guys giving different opinions on the issue of soft brakes after hard use

remember that the brake fluid is hydroclastic
which means it creates moisture
under heavy use it becomes vapor vapor is compressible
that's why your pedal feels soft
try replacing the fluid before you use the brakes that hard

but most definitelly learn to drive and balance your speed with the throttle so you don't have to abuse your brakes
s4master1 is offline  
Old 09-28-2003, 12:28 AM
  #26  
Elder Member
 
Join Date: Mar 2001
Posts: 11,968
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Not abusing brakes at Road America

Whether you call it abuse or just extreme service, it really can't be avoided.

That straight at the bottom of the pic is the longest straight on any road course in N. America.

The shorter straight in the middle of the pic is all downhill and ends in a slow 110o left turn.

The shortest "straight" is in the upper right, but the entry is the 100+ mph 45o right hander at the top of the pic (the Kink), and the straight ends with a slow 100o right turn.

Top speeds at the end of all three of these straights is nearly identical, and <u>very</u> heavy braking cannot be avoided.

<img src="http://pictureposter.audiworld.com/17157/roadamerica_aerial.jpg">
ryoung is offline  
Old 09-28-2003, 06:04 AM
  #27  
AudiWorld Super User
Thread Starter
 
Join Date: Jul 2001
Posts: 18,462
Likes: 0
Received 0 Likes on 0 Posts
Default My instructor doing 2:46's with me in the car....

....didn't pull as many braking g's as I did when I was really crancking on the brakes.

When I really stepped on them, the car just hauled to a stop, and I was running a 3:04 or so.

He used significantly less braking pressure, just started his braking a little earlier (which he would have because he was running faster times), but he would carry so much momentum through the corners and be on the gas at the apex and just driving it out of it.

pw
PaulW is offline  
Old 09-28-2003, 06:35 AM
  #28  
Elder Member
 
Join Date: Mar 2001
Posts: 11,968
Likes: 0
Received 0 Likes on 0 Posts
Default In your car or his?

And I hope you meant 2:46 :-)

The Corvette in the in-car camera video of this SCCA Speed World Challenge race at Road America spends a lot of time dicing with an Audi S4. Their clean laps were 2:25's (Wow), and that's on the Toyo T1-S spec street tire. I imagine they were 150+ mph at the end of the straights and that much harder on their brakes.

It's an interesting video. The Corvette looks like he's braking the way we did. At the end of the straights, he usually gains a couple of car lengths on most of the other cars, only to lose the advantage on the corner exits.<ul><li><a href="http://bbs.sccaproracing.com/ubb/Forum2/HTML/002381.html">Speedvision Videos</a></li></ul>
ryoung is offline  
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
kmryu
A6 (C7 Platform) Discussion
5
01-01-2013 08:13 AM
Jon-1.8t
Audi 5000 / 200 / V8 Discussion
0
03-08-2006 06:46 PM
Milpitas2.7T
S4 / RS4 (B5 Platform) Discussion
3
11-04-2002 08:55 AM
J4SON
S4 / RS4 (B5 Platform) Discussion
4
05-26-2002 03:59 PM
Monkeyboy
A4 (B5 Platform) Discussion
4
05-03-2002 07:34 AM


Thread Tools
Search this Thread
Quick Reply: Why do you think a brake pedal gets soft after repeated hard braking?


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: