I was at COTA this morning for a track day and during the 3rd session of the day, I had major brake fade 25 minutes in. The pedal went 80%
|
|
LinkBack | Thread Tools | Display Modes |
01-29-2022, 04:52 PM | #1 (permalink) |
Base Member
Join Date: May 2021
Location: Austin, TX
Posts: 123
Drives: 14 370z Sport M6
Rep Power: 4 |
WTF is wrong with my brakes?
I was at COTA this morning for a track day and during the 3rd session of the day, I had major brake fade 25 minutes in.
The pedal went 80% soft, I still had some brake pressure, so I pulled it into the pits. In the first and second sessions of the day, I did not go hard at all since the track was really cold, my tire pressures were too high, and COTA has a brand new surface in a lot of corners. COTA is a big, fast track, but isn't what I would consider really hard on brakes. There are 4 corners that you brake hard and deep in, but that is it. ~60 deg. ambient temp ~240-250 deg. oil temp (even w/ vented hood and 25 row oil cooler) 2014 Sport w/ Akebonos (obviously) Z1 2-piece front rotors, slotted Z1 1-piece rear rotors, slotted Z1 SS Lines Z1 Front brake duct cooling kit Titanium shims in the front Carbotech XP10 in front / XP8 in rear RBF600 fluid, about 3 months old, 1 previous track weekend with this fluid. I saw some brake fluid was leaking out of 3 of 4 of the caliper bleeder screws on the outside nipple, other threads on this forum say that is common and not that big of a deal and wasn't associated with brake fade. The ONLY thing I think of that could have any sort of impact is that the pads were brand new, and I used the recon session (1st session) to bed them in. It's possible I didn't bed them in well enough, but I don't know if that would cause the brakes to feel great for a few sessions, then fade to nothing. Getting really frustrated with the brakes on this Z. Does anyone know what the culprit could be? Is my expectation to be able to run a full weekend without any fade unreasonable with my setup?
__________________
"Casual" track car...NASA TX. |
01-29-2022, 06:49 PM | #2 (permalink) |
Enthusiast Member
Join Date: Dec 2010
Location: new jersey
Posts: 452
Drives: 2011 MB 370Z NISMO
Rep Power: 1246 |
Carbotech pads and z1 piece rotors don’t work too well in my experience. Could not make it past one track day without hint of fade and vibration after the track day. I gave up and bought stoptech 6 piston trophy kit for the front and never had any issues after. Was worried about brake balance but the rear stock akebonos are keeping up no problem. It seems many members to have had issues with carbotech/z1 on the track.
|
01-29-2022, 06:57 PM | #4 (permalink) | |
Base Member
Join Date: May 2021
Location: Austin, TX
Posts: 123
Drives: 14 370z Sport M6
Rep Power: 4 |
Quote:
If a $3,800 brake kit is needed just to make the Z get through a full track day, I'm about to buy a Miata...
__________________
"Casual" track car...NASA TX. |
|
01-29-2022, 07:11 PM | #5 (permalink) | |
Base Member
Join Date: May 2021
Location: Austin, TX
Posts: 123
Drives: 14 370z Sport M6
Rep Power: 4 |
Quote:
I'm a novice. Still have a lot to learn, but not sure if there's a whole you can do to keep things cool braking after a .62 mile straightaway into a 90-degree corner.
__________________
"Casual" track car...NASA TX. |
|
01-29-2022, 07:54 PM | #6 (permalink) |
Ronin Samurai - Assassin
Join Date: Dec 2011
Location: Fayettenam,Pennsyltucky
Age: 68
Posts: 35,218
Drives: 2011 Nismo GM 6M
Rep Power: 2684438 |
Bleed your brakes. And try a different pad. Z1 rotors are not high on my list of rotors. If you want 2 piece rotors for the track. You have to step up.
__________________
浪人 - 殺し屋 "The Difficult Anytime, The Impossible By Appointment Only" http://www.the370z.com/members-370z-...o-journal.html |
01-29-2022, 09:12 PM | #7 (permalink) | |
Enthusiast Member
Join Date: Dec 2010
Location: new jersey
Posts: 452
Drives: 2011 MB 370Z NISMO
Rep Power: 1246 |
Quote:
Building a track car and getting faster by starting to push limits turns into never ending money pit especially with 370z. |
|
01-30-2022, 02:30 AM | #8 (permalink) |
A True Z Fanatic
Join Date: Dec 2009
Location: 03350 Australia
Posts: 1,514
Drives: 09 Nissan 370Z M6
Rep Power: 39973 |
Brake temps are the issue - have you fitted ducted cooling air from the front fascia to the centre/back of the rotors ?
Tracking for 25minutes even with modest skill is about the same as driving hard down a mountain .......... You do need to look after your brakes and that starts with managing temps for rotors, pads and calipers/fluid And to answer your question, there is nothing wrong with your brakes, they've just got too hot. |
01-30-2022, 11:41 AM | #9 (permalink) | |
Base Member
Join Date: May 2021
Location: Austin, TX
Posts: 123
Drives: 14 370z Sport M6
Rep Power: 4 |
Quote:
So -- riddle me this. What actually happened to cause the fade? Did the fluid boil? Did the rotor or pad temperature get too hot to be effective? Would the brakes have been fine for another session after they cooled?
__________________
"Casual" track car...NASA TX. |
|
01-30-2022, 01:53 PM | #10 (permalink) | |
A True Z Fanatic
Join Date: Jun 2014
Location: Ga
Posts: 13,834
Drives: 2013 Nismo 370z
Rep Power: 2684392 |
Quote:
|
|
01-30-2022, 03:33 PM | #11 (permalink) | |
A True Z Fanatic
Join Date: Dec 2009
Location: 03350 Australia
Posts: 1,514
Drives: 09 Nissan 370Z M6
Rep Power: 39973 |
Quote:
You would need to bleed the brakes before the next session. I regularly track my Z (and race an historic V8 MG) and baseline brake fettling was to remove the backing plate, install 3" ducting from the front fascia (mine is an '09 model and there is a neat hole in the fascia to use) and I use a variety of "club-spec" pads - I do not use a full race pad in the Z because they are too aggressive - the Z is not my race car after all. Track day fettling is to install the track pads, bleed the brakes, stiffen up the shocks and go have fun in 20-minute blocks. |
|
01-30-2022, 03:40 PM | #12 (permalink) |
A True Z Fanatic
Join Date: Oct 2011
Location: Knoxville
Age: 71
Posts: 3,190
Drives: 12 370Z BK Cherry M6
Rep Power: 649540 |
I had brake fade problems too, for brake fluid I went with RBF660 fluid,
I also have the Titanium shims in the front, and brake cooling. I did do a track day at mid-ohio and one at Road Atlanta did not have any problems.. 1 piece front and rear discs... just my experience
__________________
Lots of Changes the Z needs to be driven and driven hard for the car lives for it |
01-30-2022, 07:11 PM | #13 (permalink) | |
Base Member
Join Date: May 2021
Location: Austin, TX
Posts: 123
Drives: 14 370z Sport M6
Rep Power: 4 |
Quote:
__________________
"Casual" track car...NASA TX. |
|
01-30-2022, 08:26 PM | #14 (permalink) |
A True Z Fanatic
Join Date: Aug 2012
Location: NW, AZ
Posts: 9,330
Drives: 10 Nissan 370z Nismo
Rep Power: 2684385 |
Your pads are fine, I used the same brake pad and rotor combination with no problem. Gloc, Winn and Hawk are few that people use. COTA is hard on brakes because it is high high speed course that requires long hard braking into several turns. I would change out your rotors as some have suggested and see if that makes a difference. If you don't want to go all out with a quality two pieces rotor like Racing Brake, the get a good solid rotor such as Frozen or Stop Tech.
The other issue you may experience, is ice mode. Many of experience it and it is way worse than brake fade. Some of us have swapped out the Nissan ABS system for the BMW MK60 ABS system. Sent from my SM-G965U using Tapatalk
__________________
Fast Intentions TT Installed and Tuned by Seb at SpecialtyZ 610whp 560tq:|Fast Intentions 3" TT-TDX|SpecialtyZ/Fast Intentions 72 Row Oil Cooler|SZ 6 Puck Clutch & Flywheel|3GsCustoms|Z1|Wavetrac|Hotchkis|Whiteline |Blitz|Fortune Auto 500|Fujimura|SPL|H&R|TK|TWM|RPM Rollbar|Sparco|Next Level Performance|TrackSpec|AeroFlow Dynamics|Pioneer| |
01-30-2022, 11:44 PM | #15 (permalink) |
A True Z Fanatic
Join Date: Apr 2011
Location: Sacramento
Posts: 3,235
Drives: 15 370Z Nismo 6MT
Rep Power: 214100 |
This page collects some data on performance brake fluid:
https://parsbrorc.com/?page_id=33 Looks like you can bump up to Endless RF650, Torque RT700, or Castrol SRF Also, as others suggested, try either solid rotors with the cryo treatment or the racing brake 2pc rotors, which are thicker than Z1’s. I believe it’s 32mm vs 28mm
__________________
OptionZero Build Thread Last edited by OptionZero; 01-30-2022 at 11:50 PM. |
Bookmarks |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
[WTB] WTB: looking sport brakes or anni red brakes | Z-Roc | Parts for sale (Private Classifieds) | 0 | 03-21-2014 03:37 PM |
Brakes, brakes, any deals on brakes? | zFire | Wanted | 9 | 03-11-2011 09:40 PM |
sport brakes painted akebono brakes | kensin0429 | Exterior & Interior | 6 | 08-23-2009 11:06 PM |
Touring Brakes vs Base Brakes | hey32g | Brakes & Suspension | 7 | 07-19-2009 12:55 PM |