Brake fade

[Robo]

Hi All,

I have upgraded (R33 gts-t power = 180 rwkw's):

-DBA slotted rotors

-Bendix Ultimate pads

-upgraded brake fluid (Dot 5.1)

I'm sure if you push any car you will expeirence fade of some sort...

Just recently doing a bit of "brake testing"..

With my current set up I can do the following (back to back and sparing minimal time between each stop):

- 120-0 kph

- 100-0 kph

- 80-0 kph

- 80-0 kph

- 80-0 kph

- maybe one more 80-0 (can't remember).

I noticed that I could still brake but the pedal started to go further down (like you had to push further to stop it) and the braking power was about 60%).

I assume it is the pads that were starting to fade (as I could smell them).

Any one know if this is any good or should they still be braking at 100%?

Best regards

Rob

Ps. never been on the track

[Roy]

With my current set up I can do the following (back to back and sparing minimal time between each stop):

Sounds like your car is braking/stopping pretty well...

Keep in mind that when you are driving at a track, about the slowest your car is going to go is the occasional 60km/hr corner, wiht plenty of higher speed stuff in between.

This means that your brakes will most likely be getting a breather between stops with some good airflow to aid cooling, which will in tun ward off fade.

Your test would seem pretty tuff, with the only chance to brakes having got to get any cooling is the 5-6seconds of acceleration between application.

[jlnewton]

I have the same brake setup as you with the dba 4000 slotted rotors fr&r and the ultimate pads. I have yet to notice any real fade yet at the track up at Queensland Raceway. The 7 lap sprints we do have yet to show fade so I am happy with that. I am not pushing as much power as you. I am sure if you go to the track as, Roy said, you would take longer to notice fade with all the high speed stuff in between, but I am sure after 20 laps they would be feeling the strain.

[predator]

hmmm.. I have slotted/drilled rotors and newish brake pads.

I have noticed it quite a bit, that as they heat up braking performance is definitely reduced. I guess that is just part of driving any form of performance car, but it definitely is something to be careful of and always take into account. While I have similar power figures, and also I don't have much trouble stopping from 100->0 in about 30m or so - when warmed up, the performance is greatly reduced, maybe up to 50m.

A couple of times this has come to my attention taking a corner too hard, or stopping from a hard sprint to rest - when you expect one braking distance, and what happens is another. Luckily it has been safe each time, but due to the nature, it never is too constant.

[benm]

I would highly recommend a set of RB74 pads for the front (www.racebrakes.com.au). Because the front does most of the work you want to have some good gear to help this and the RB74's will deffinetly last longer than a set of Bendix pads.

They cost me $130 for the front set (but I paid extra to have RaceBrakes bed them in for me as I wanted it done correctly).

Apart from that you could get Braided lines (front) which cost me $420 and they will/should reduce fade also.

[Roy]

Do braided lines help reduce fade???? or do they just imporve the feel and control of the pedal.

[benm]

My understanding is/was that normal brake lines can expand from heat where as the braided lines cannot.

[Robo]

Thanks all for your responses and information..

Just wanted to check if my brakes are up to spec.

Also thinking about the brake pedal itself. Would one of those brake support brackets (I have seen them in the engine bay under/next to the brake fluid - I think they stop flex or something like that) help my case?

Best regards

Rob

[Roy]

Yeh the rubber lines can expand with pressure/heat but i think this impacts the feel of the brakes thru the pedal, not the actual limit in which fade starts to appear( Boiling fluid or pads/rotors outside ideal temp range)

I have wanted to get one of those braces as well, i have seen strut braces that incorporate them... but couldnt bring myslef to spend the couple of hundred they ask for them, when if i got off my a55 you could make one for less then $50

[Duncan]

I think that sounds like *very* healthy brakes if you did the stops straight after each other....if you were fading after 3 or 4 I would be worried.

[Sydneykid]

Hi Robo, that's exactly the sort of superior braking performance that I would expect from your set up. In a circuit environment we have found the limiting factor to be tyres rather than this type of brake set up and we use R type tyres. The brakes work far better than the tyres do. Even after 10 laps we can still lock up the tyres.

[slip]

RB74's have done well for me, the only things that have occured under hard use are...

1. need to pump up the pedal before the corner sometimes under hard use

2. cracked some dba r32 gtst rotors

No major fade experienced yet.

They work a better with a bit of heat in them.

[benm]

ahh just the thread I was searching for....

Got the mechanic to re-bleed my brakes today in an effort to try and fix the inconsistent pedal. Before I dropped it off to him it was:

pump+pump=brake, pump+pump=brake.

Now after the bleed the pedal is just consistently low (grrrr x10000) but it still stops very nicely. To test it I wanted to murder them abit to see what they really felt like (I also wanted to test the K&N Panel Filter I put in so I wasn't exactly accellerating slowly between stop) so I did:

60->20km/h

60->20km/h

60->20km/h

stop and turn around

60->20km/h

60->20km/h

60->20km/h

stop and turn around

100->20km/h

100->20km/h

100->20km/h

stop and turn around

130->20km/h

130->0km/h

stop and turn around

60->20km/h

60->20km/h

60->20km/h

(90sec of 50km/h driving not using the brakes at all)

80->20km/h

80->20km/h

stop at lights.

...then I just drove home normally the rest of the way (about 3km). The brakes smelt quite nice when I got home

Now whilst I couldn't notice my pedal getting any lower I was hitting the ABS on the 3rd set of 60->20km/h braking as it was a different road (the smooth type of tarmac) where as first 4 sessions were all done on the rocky type of tarmac so I guess the brakes were still biting pretty hard at that stage. Infact... I think they just wanted to keep on going n going but I was starting to annoy afew people on that stretch of road so I decided to go home.

Now If I can get the mechanic to workout why the pedal is consistently low and fix it back to being consistently firm i'll be quite a happy camper.

[slip]

see if there is any adjustment up near the pedal box in the footwell. It may be flexing or bent as well. Luke has a strong clutch in his gts4, he actually bent, then snapped the pedal box, had to get a custom one fabricated for 4-500 bucks. His clutch used to engage just off the floor, now its up higher, and has heaps better feel.

[Roy]

Now after the bleed the pedal is just consistently low (grrrr x10000) but it still stops very nicely. To test it I wanted to murder them abit to see what they really felt like (I also wanted to test the K&N Panel Filter I put in so I wasn't exactly accellerating slowly between stop) so I did:

   

  60->20km/h

  60->20km/h

  60->20km/h

  stop and turn around

  60->20km/h

  60->20km/h

  60->20km/h

  stop and turn around

  100->20km/h

  100->20km/h

  100->20km/h

  stop and turn around

  130->20km/h

  130->0km/h

  stop and turn around

  60->20km/h

  60->20km/h

  60->20km/h

  (90sec of 50km/h driving not using the brakes at all)

  80->20km/h

  80->20km/h

  stop at lights.

   

  ...then I just drove home normally the rest of the way (about 3km). The brakes smelt quite nice when I got home

So you were doing that all on the one street... locals must have thought an epileptic was driving your car

[benm]

Nah a total of 3 streets. The first 4 sessions was on the 1 street, the 5th was on another road and the 6th was on another road again.

I felt like an epileptic after all that braking hahah.

[drifto]

Also thinking about the brake pedal itself. Would one of those brake support brackets (I have seen them in the engine bay under/next to the brake fluid - I think they stop flex or something like that) help my case?

Yes, i have one made by CUSCO which is seperate to my strut tower brace. It stops or helps firwall flex and there fore improves pedal feel but not ultimate stopping distance or time.

I also found it is hard to narrow down the culprit of a braking problem because it is such a complex system.

I had poor braking at a track day after spending $1400 on a brake upgrade that included:

EBC drilled and slotted rotors (original size)

EBC RED STUFF front pads

EBC GREEN STUFF rear pads

DOT 5.1 race fluid

This is the same parts used in the Monaros that raced Targa Tassy by Brock & the other Guy!

On the track the red front pads weren't getting to operating temp and biting properly so the green rears were overworking. The rears then cooked and faded causing the fronts to do all the work. They then got to hot and faded. After taking them back in disgust the installer he even said the hubs had caught on fire :flamed: at some stage by the discoulouring of the hub & inside of the rims.

The point is a system needs to be matched to a paticular car and the conditions it's driven in.

I drove ROY's 32 at same track day and was blown away by the stopping power. Well done RACE BRAKES! :aroused:

[benm]

My car is going to be back at Race Brakes next week getting a full inspection because my local Brake mechanic cannot find any problems (and wants to get an independant NRMA inspection just to make me happy.... which im far from)

[mist]

hey guys, would just like to put in that sometimes poor braking could be due to calipers that are in poor condition. Many of our skylines are more than 5 years old, and many calipers are in need of a rebuild. There's a caliper rebuild kit (seals, etc) available from Nissan, can't remember the cost exactly but I think it's about a couple of hundred bucks. Will transform ur braking if your calipers are a little tired...

[benm]

Done that