Brake or Pedal Fade on Track

Powerslide · 09-15-2021, 08:33 PM

I just experienced brake pedal fade on track for first time this weekend in tracking the F80 since 2016 (average 3-4 track events per year since then).

I have the stock rotors and calipers - with PFC08 pads. I do mot have stainless steel brake lines - and I get my brake fluid swapped out once per year with the Super DOT 4 fluid (first track event of the year with this fluid).

I'm trying to determine the potential causes of this - fluid is just barely below maximum level - and my lap times were no faster than before and same category of tires (Michelin Cup 2). Maybe just need stainless steel brake lines? Other ideas or suggestions? Thanks in advance,

FaRKle! · 09-15-2021, 09:24 PM

I'd guess that your Super DOT 4 fluid is boiling. It doesn't have a very high boiling point (about 100F lower) compared to the typical track fluids (Motul/Castrol).

dawei213 · 09-15-2021, 09:31 PM

Quote:

Originally Posted by FaRKle!

I'd guess that your Super DOT 4 fluid is boiling. It doesn't have a very high boiling point (about 100F lower) compared to the typical track fluids (Motul/Castrol).

Sounds like it. Changing out to Motul/Castrol prior to next track event is probably the most cost effective way to see if the issue presents itself again.

Suds · 09-15-2021, 10:05 PM

M4, I am using Castrol SRF Dot 4 changed every 12 months, stock brakes and lines with PFC08 brakes, no problems.
I ran SCCA time attack last month with no problems.

Driver407 · 09-15-2021, 11:07 PM

As others said. Once you get some nice fluid in, you will be golden. Stock setup with pfc and nice fluids can easily last a long 45 minute session and not break a sweat.
Stainless is more of a luxury than any true gain, I was a little let down when i got them. I would say it negligible.

CanAutM3 · 09-16-2021, 09:53 PM

What do you mean by "brake pedal fade" ?

Is it that your pedal gets long but you still have braking power?

Or is it that you don't seem to get enough braking power despite pressing hard on the pedal?

jmg · 09-17-2021, 01:23 PM

Quote:

Originally Posted by Powerslide

I just experienced brake pedal fade on track for first time this weekend in tracking the F80 since 2016 (average 3-4 track events per year since then).

I have the stock rotors and calipers - with PFC08 pads. I do mot have stainless steel brake lines - and I get my brake fluid swapped out once per year with the Super DOT 4 fluid (first track event of the year with this fluid).

I'm trying to determine the potential causes of this - fluid is just barely below maximum level - and my lap times were no faster than before and same category of tires (Michelin Cup 2). Maybe just need stainless steel brake lines? Other ideas or suggestions? Thanks in advance,

Get Castol SRF or Motul 660 before you looking into brake lines.

Brake fluid and pads have a temperature in which performance will start to fall off steeply.

When brake fluid goes above boiling temps, you will feel sponginess.

When brake pads get too hot, you will get glazing and/or that deep sinking feeling in your gut of the car not stopping like you want it to. Glazing will lead to deposits which lead to vibrations during braking along with increase in braking distance.

NYG · 09-17-2021, 02:34 PM

It's all going to lead up to you getting a BBK. Skip all the in-between, trust me.

Powerslide · 09-17-2021, 04:39 PM

Quote:

Originally Posted by CanAutM3

What do you mean by "brake pedal fade" ?

Is it that your pedal gets long but you still have braking power?

Or is it that you don't seem to get enough braking power despite pressing hard on the pedal?

It would be longer pedal travel - any insights you could provide would be great!

jmg · 09-17-2021, 05:07 PM

Quote:

Originally Posted by Powerslide

It would be longer pedal travel - any insights you could provide would be great!

That's air in the system as a result of boiling your fluid. Definitely switch to Castro SRF or Motul 660.

CanAutM3 · 09-17-2021, 05:44 PM

Quote:

Originally Posted by Powerslide

It would be longer pedal travel - any insights you could provide would be great!

Have you considered it could be caused by pad knock back?

Powerslide · 09-17-2021, 08:48 PM

Quote:

Originally Posted by CanAutM3

Quote:

Originally Posted by Powerslide

It would be longer pedal travel - any insights you could provide would be great!

Have you considered it could be caused by pad knock back?

I have not considered that - but either way I think I need to upgrade to Castrol SRF or the Motul (not sure about pros/cons of each - but they both seem to be great options compared to what I'm using right now)!

sc_tr0jan_m3 · 09-18-2021, 07:41 PM

FCP stocks motul so grab 2 bottles there and fluid flushed will be free w warranty!

09-15-2021, 08:33 PM	#1
Powerslide Colonel 1097 Rep 2,287 Posts Drives: 2018 F80 ZCP Join Date: Nov 2007 Location: Chicago Illinois USA iTrader: (0)	Brake or Pedal Fade on Track - stock rotors PFC08 Pads? I just experienced brake pedal fade on track for first time this weekend in tracking the F80 since 2016 (average 3-4 track events per year since then). I have the stock rotors and calipers - with PFC08 pads. I do mot have stainless steel brake lines - and I get my brake fluid swapped out once per year with the Super DOT 4 fluid (first track event of the year with this fluid). I'm trying to determine the potential causes of this - fluid is just barely below maximum level - and my lap times were no faster than before and same category of tires (Michelin Cup 2). Maybe just need stainless steel brake lines? Other ideas or suggestions? Thanks in advance,
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09-15-2021, 09:24 PM	#2
FaRKle! Brigadier General 4007 Rep 3,535 Posts Drives: 328d Wagon, M2 Comp, i4 eD35 Join Date: Sep 2016 Location: Bay Area, CA iTrader: (4) Garage List 2023 BMW i4 eDrive 35 [0.00] 2017 BMW 328dx Wagon [0.00] 2021 BMW M2 Competi ... [0.00]	I'd guess that your Super DOT 4 fluid is boiling. It doesn't have a very high boiling point (about 100F lower) compared to the typical track fluids (Motul/Castrol). __________________ -328d Wagon Build Log (with helpful reference links) -My YouTube Channel for some of the best DIYs and in depth information Please don't PM me for suspension recommendations unless interested in paid private consultations.
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09-15-2021, 10:05 PM	#4
Suds /M Enthusiast 1597 Rep 1,617 Posts Drives: Responsiblish Join Date: Aug 2010 Location: Lone Star State iTrader: (1)	M4, I am using Castrol SRF Dot 4 changed every 12 months, stock brakes and lines with PFC08 brakes, no problems. I ran SCCA time attack last month with no problems. __________________ 2019 M2 Comp, Alpine White, DCT, track car build, 1/2 cage, AP Racing Brakes & Nitron Coilovers, BM3 Stage 1 93 Oct. 2018 Porsche Cayman GTS, Night Blue Metalic, PDK, COBB tuned 93 Oct. 2004 Audi A4 Avant USP 6mt, RS4 clutch, built motor, Garrett GT3071r "Big Ass Turbo" Motoza Tune
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09-15-2021, 11:07 PM	#5
Driver407 Second Lieutenant 220 Rep 248 Posts Drives: 16' F80 M3, 02' E46 M3 Join Date: Jun 2019 Location: CA iTrader: (2)	As others said. Once you get some nice fluid in, you will be golden. Stock setup with pfc and nice fluids can easily last a long 45 minute session and not break a sweat. Stainless is more of a luxury than any true gain, I was a little let down when i got them. I would say it negligible. __________________ '16 F80 M3 DCT TC Kline coilovers and camber plates, Apex 18" EC-7, Conti ECF 295r/275f, monoball thrustarms, SPL toe arms, Powerflex diff bushings/bracket, AP Racing 9660, Project Mu H21, Spiegler brake lines, AA midpipe, VTT crankhub, VRSF charge/j pipe, Turner tray, BM3 CS Youtube: Driver407
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09-16-2021, 09:53 PM	#6
CanAutM3 General 21115 Rep 20,741 Posts Drives: 2021 911 turbo Join Date: Jan 2012 Location: Montreal iTrader: (1) Garage List 2022 Audi RS6 [10.00] 2021 Porsche 911 turbo [10.00]	What do you mean by "brake pedal fade" ? Is it that your pedal gets long but you still have braking power? Or is it that you don't seem to get enough braking power despite pressing hard on the pedal? __________________ Porsche 911 turbo 2021 992 GT Silver Previous cars: M4cs 2019 F82 Limerock Grey / M4 2015 F82 Silverstone / M3 2008 E92 Silverstone / M3 2002 E46 Carbon Black
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09-17-2021, 02:34 PM	#8
NYG Brigadier General 10580 Rep 3,643 Posts Drives: Corvette Z06 Join Date: Feb 2017 Location: Brooklyn, NY iTrader: (0)	It's all going to lead up to you getting a BBK. Skip all the in-between, trust me.
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09-18-2021, 07:41 PM	#13
sc_tr0jan_m3 Lieutenant Colonel 517 Rep 1,730 Posts Drives: 2018 Grigio Telesto F80 M3 DCT Join Date: Feb 2009 Location: Dallas, TX iTrader: (0)	FCP stocks motul so grab 2 bottles there and fluid flushed will be free w warranty! __________________ 2018 Grigio Telesto F80 M3 DCT \| :: Bone Stock :: 2004 Titanium Silver E46 M3 6 Speed \| :: Track Car ::
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