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-   -   Brake fade is getting out of hand (https://www.ft86club.com/forums/showthread.php?t=146759)

Jstyle 09-03-2021 07:11 AM

Brake fade is getting out of hand
 
Over the last year I’ve definitely learned I could control brake fade… to a certain extent by not stabbing the brakes (which is just a good idea period and a part of learning), better cool down laps… etc… etc… etc…

Well at Summit Point Main yesterday, it didn’t matter how much I babied the brakes I had nothing by the end of the day. I kept having to back my brake points further and further and further back. On top of that my rotors are pretty warped at this point as well… The pulsing going into turn 1 was intense by the end of the day :bonk:

So since I have to buy and oil cooler now I’m just not in a place where I can buy that AND a BBK at the moment. Will buying just a nice set of stock sized rotors that are drilled and/or slotted help? Any recommendations on which rotors to get? Also I still have the stock brake lines which I haven’t changed yet because the car has just a little over 2k miles so I haven’t even crossed that bridge yet, could that be causing some of it?

I already have XP10’s in the front and XP8’s in the back.

soundman98 09-03-2021 08:06 AM

what fluid are you running?

Jstyle 09-03-2021 08:10 AM

Quote:

Originally Posted by soundman98 (Post 3462682)
what fluid are you running?

Motul660

NoHaveMSG 09-03-2021 08:49 AM

Brake fade is getting out of hand
 
The pulsing is not warped rotors. It is the pads depositing material on them in uneven smears. Carbotech pads suck. I had the same issue with XP10s. Do you you have brake ducting ?

Vesartis 09-03-2021 08:51 AM

My obvious guess is that it sounds like your fluid needs to be bled or changed if the pedal is getting soft. Pulsing or "warping" usually is a pad deposit problem rather than the rotor itself, especially if it goes away on the street. The way to manage that would be to get a more heat resistant pad. Yours might be fine, but there might be more exotic options. (CSG Spec, etc.) As far as rotors, I've heard that financially it makes more sense to stick with blanks and replace more frequently, because the cooling benefit from fancy rotors alone isn't much.

A cheap stopgap would be a makeshift air deflector on the lower control arm that would divert air to the front brakes. There's no fully premade solution, but it's a concept used in other cars. I use a Porsche GT3 part that I cut up a bit and zip tied, and it extended my hot laps maybe 15-20%.

Are you turning off traction control? Doing the pedal dance when comfortable? With traction/stability on, the system will be overusing the brakes very quickly. Even with it "off", the rear brakes are being used a lot, and can overheat if you are driving aggressively.

Jstyle 09-03-2021 09:13 AM

No I don’t have ducting at all. Maybe that’s a good next step. Now that you mention it I don’t have any shake or pulsing on the street.

ZDan 09-03-2021 09:15 AM

Above questions all good ^^^ How often do you bleed, any nannies on, track mode, 3-second hold on TC button? etc.
For me, 3-second hold worked fine at 11/10ths and beyond. But "Track Mode" is too intrusive...

IMO should go with square pads, it's possible that with XP10/XP8 the rears aren't helping out enough. Never understood why so many insist on "staggered" pads, it just gives too much front bias in the only cases I'm familiar with (240Z, FD, S2000, BRZ)

Also worth noting I've *never* had any issues just running off-the-shelf name-brand DOT4 or DOT5.1 from AutoZone/PepBoys/etc. even in the 550hp FD. In my limited experience with them, "race" brake fluids don't seem to last nearly as long before pedal starts to feel soft. I can get 6+ track days out of "normal" brake fluid.

blsfrs 09-03-2021 10:04 AM

I ran Summit Point last fall. I have a n/a FRS with stock suspension and brakes. I have xp8, blank Ebay rotors on all 4 corners, and used Motul 600. I do have braided "soft" lines. I've run VIR with the same set up and have no problems. I try not to use my brakes on the cool down and I don't set my ebrake when parked in the paddock. Maybe the staggered set up is causing the problem.

rice_classic 09-03-2021 12:47 PM

Assuming no brake ducts.

Street pads + lack of ducts is a pretty inevitable outcome. You'll have to step up your hardware.

Buy proper race pads and a set of brake ducts. If you can't do ducts yet, start with proper pads. Before the event grab your 14mm wrench and swap in your track only pads (they'll be fine on the drive to the track) and you'll enjoy your day much more.

Lots of good options here too: Raybestos ST series, CSG, GLOC, Cobalt XR1 etc.

NoHaveMSG 09-03-2021 01:07 PM

Brake fade is getting out of hand
 
This is XP10 on BBK. Same compound F&R. You can see the smears all over the friction rings.

https://uploads.tapatalk-cdn.com/202...c4082ffe5d.jpg

blsfrs 09-03-2021 01:45 PM

Quote:

Originally Posted by Vesartis (Post 3462695)
My obvious guess is that it sounds like your fluid needs to be bled or changed if the pedal is getting soft. Pulsing or "warping" usually is a pad deposit problem rather than the rotor itself, especially if it goes away on the street. The way to manage that would be to get a more heat resistant pad. Yours might be fine, but there might be more exotic options. (CSG Spec, etc.) As far as rotors, I've heard that financially it makes more sense to stick with blanks and replace more frequently, because the cooling benefit from fancy rotors alone isn't much.

A cheap stopgap would be a makeshift air deflector on the lower control arm that would divert air to the front brakes. There's no fully premade solution, but it's a concept used in other cars. I use a Porsche GT3 part that I cut up a bit and zip tied, and it extended my hot laps maybe 15-20%.

Are you turning off traction control? Doing the pedal dance when comfortable? With traction/stability on, the system will be overusing the brakes very quickly. Even with it "off", the rear brakes are being used a lot, and can overheat if you are driving aggressively.


Do you have pictures of your GT3 deflectors? I just got a set and have had to trim the crap off the front side to clear my wheels. I haven't been able work out a ziptie configuration to get them to stay in place. Did you leave your backing plates intact?

Jstyle 09-03-2021 02:19 PM

So I just pulled off the wheels to check the pads and they are absolutely smoked. Like almost nothing left. The brakes got so hot it melted the rubber bleed valve cover to the brake. I think maybe it’s because there was almost no pad left which had nowhere to dissipate heat… Maybe. My back XP8’s are still almost full of life, my 10’s are just shot. I guess time for a new pad. I’ll check into ducting as well.

Vesartis 09-03-2021 02:35 PM

Quote:

Originally Posted by blsfrs (Post 3462787)
Do you have pictures of your GT3 deflectors? I just got a set and have had to trim the crap off the front side to clear my wheels. I haven't been able work out a ziptie configuration to get them to stay in place. Did you leave your backing plates intact?

Pics

They definitely aren't sturdy. I bent the little triangle of the dust shield but I think ideally you want to take them off. I don't run them since switching to CSG pads, since they ended up makin the braking feel inconsistent.

CSG Mike 09-03-2021 03:52 PM

Quote:

Originally Posted by Jstyle (Post 3462672)
Over the last year I’ve definitely learned I could control brake fade… to a certain extent by not stabbing the brakes (which is just a good idea period and a part of learning), better cool down laps… etc… etc… etc…

Well at Summit Point Main yesterday, it didn’t matter how much I babied the brakes I had nothing by the end of the day. I kept having to back my brake points further and further and further back. On top of that my rotors are pretty warped at this point as well… The pulsing going into turn 1 was intense by the end of the day :bonk:

So since I have to buy and oil cooler now I’m just not in a place where I can buy that AND a BBK at the moment. Will buying just a nice set of stock sized rotors that are drilled and/or slotted help? Any recommendations on which rotors to get? Also I still have the stock brake lines which I haven’t changed yet because the car has just a little over 2k miles so I haven’t even crossed that bridge yet, could that be causing some of it?

I already have XP10’s in the front and XP8’s in the back.

That's a very entry level, beginner setup, which you're clearly FAR beyond, if you've already realized and learned how to modulate FADE, let alone just braking.

Try the CSG C2 front and rear. Yes, non-staggered.

If you want to get even more life and capacity, go CE2 front C2 rear.


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