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-   Suspension | Chassis | Brakes -- Sponsored by 949 Racing (https://www.ft86club.com/forums/forumdisplay.php?f=59)
-   -   Brake failure at the race track (https://www.ft86club.com/forums/showthread.php?t=136137)

CSG Mike 08-05-2019 04:35 PM

Quote:

Originally Posted by Gt86Force (Post 3244636)
Go with stock rotors, steel brake lines, RBF600 (or similar) and Ferodo DS2500.
I've tracked a lot with that combo without issues, and stil daily driving the car.

"works for me =/= works for you"

CSG David 08-05-2019 05:00 PM

Quote:

Originally Posted by biggie (Post 3244750)
Brake lines are on their way (stoptech), already using Castrol SRF (should be even better than motul) and I think I made up my mind and I'm going for Carbotech XP10.

Still debating about rotors...slotted or plain!?

We can help supply you with the correct parts as necessary. :)

biggie 08-05-2019 05:23 PM

Quote:

Originally Posted by CSG David (Post 3244793)
We can help supply you with the correct parts as necessary. :)

You've got PM :)

Gt86Force 08-06-2019 07:17 AM

Quote:

Originally Posted by CSG Mike (Post 3244779)
"works for me =/= works for you"

Yes, you're absolutely right!
But from my experience that is the minimum config. for tracking your car.
I've been to Monza (a heavily brake intense track in Italy, it's one of the fastest in europe) without major issues. There was fading (a lot) but nothing dangerous, you can sense it 3 corners before the main straight. I've never found myself completely without brakes.

I think the DS2500 (or similar compound) is the minimum if you track your car, and if you are not using semi tires, you're on stock power and still use the car on the street BBK or racing compounds are overkill or sometimes dangerous (on the street).

CSG Mike 08-06-2019 03:08 PM

Quote:

Originally Posted by Gt86Force (Post 3244995)
Yes, you're absolutely right!
But from my experience that is the minimum config. for tracking your car.
I've been to Monza (a heavily brake intense track in Italy, it's one of the fastest in europe) without major issues. There was fading (a lot) but nothing dangerous, you can sense it 3 corners before the main straight. I've never found myself completely without brakes.

I think the DS2500 (or similar compound) is the minimum if you track your car, and if you are not using semi tires, you're on stock power and still use the car on the street BBK or racing compounds are overkill or sometimes dangerous (on the street).

Fading is a major issue, especially for a novice that may not realize they are fading, and then suddenly finding themselves without brakes.

In fact, brake pedal behavior change is not acceptable at all!

Imagine if your street car on the street had a variable brake pedal and you sometimes have to press the pedal further/harder than other times! :eyebulge:

biggie 08-06-2019 03:19 PM

Quote:

Originally Posted by CSG Mike (Post 3245137)
Fading is a major issue, especially for a novice that may not realize they are fading, and then suddenly finding themselves without brakes.

In fact, brake pedal behavior change is not acceptable at all!

Imagine if your street car on the street had a variable brake pedal and you sometimes have to press the pedal further/harder than other times! :eyebulge:

Truth be told, I did noticed the brakes were starting to fade but I did not expected to lose them completely. So I'm still a noob, I guess :sigh:

wparsons 08-06-2019 04:27 PM

It's a bit mind blowing to read people saying they'll feel pad fade for multiple corners before they'll back off. If the pads are overheated, back off and let them cool before you end up in a wall.

Icecreamtruk 08-06-2019 04:47 PM

Quote:

Originally Posted by wparsons (Post 3245175)
It's a bit mind blowing to read people saying they'll feel pad fade for multiple corners before they'll back off. If the pads are overheated, back off and let them cool before you end up in a wall.

I did that mistake once, felt the brakes faded, was 1 corner away from finishing a lap, decided to finish it anyways. That one corner was the scariest moment I've lived so far, specially since it ended on a wall. Decided to send the car sideways to get it to stop, worked but I think it was pure luck. Never again :slap:

biggie 08-06-2019 04:57 PM

Quote:

Originally Posted by wparsons (Post 3245175)
It's a bit mind blowing to read people saying they'll feel pad fade for multiple corners before they'll back off. If the pads are overheated, back off and let them cool before you end up in a wall.

People makes mistakes, the important thing is to not repeat them. I certainly learned my lesson.

Anyway, just ordered Stoptech slotted rotors and Carbotech XP10 pads (already got the stoptech brake lines). Hope I took the right decision...

CSG David 08-06-2019 06:08 PM

Quote:

Originally Posted by wparsons (Post 3245175)
It's a bit mind blowing to read people saying they'll feel pad fade for multiple corners before they'll back off. If the pads are overheated, back off and let them cool before you end up in a wall.

It's all about lap times for people, but the real winner is the person who can drive their car home in the same condition they brought it to the track.

CSG Mike 08-06-2019 06:12 PM

Quote:

Originally Posted by biggie (Post 3245190)
People makes mistakes, the important thing is to not repeat them. I certainly learn my lesson.

Anyway, just ordered Stoptech slotted rotors and Carbotech XP10 pads (already got the stoptech brake lines). Hope I took the right decision...

Great entry level pad!

Support the folks who support you! :thumbsup:

JRitt 08-07-2019 03:00 PM

Gents,
As an FYI...we recently took the Ferodo DS2500 to 1500°F on our dyno and they didn't fade. As noted by others, they are a fantastic hybrid pad. That said, switching between street and track pads is still optimal.

churchx 08-07-2019 04:04 PM

JRitt: btw, as you guys have brake dyno .. what do you think of making some testing roundup on multiple cross vendor pads? One thing is vendor charts, that are hard to cross-compare just like power dyno charts with no baseline and from different dyno rigs, another would be real dyno testing/combined chart of friction graphs vs temps of multiple vendor, multiple class (hybrid/track/endurance) pads ..
From what i understand, no real usage on car no matter how good driver will get close to reducing margin of error and repeatability/consistency of what brake dyno may provide?

NoHaveMSG 08-07-2019 04:22 PM

Also seeing the consistency of the coefficient of friction across the temperature range :drool:

I am sure that would be asking a lot though :D

Tristor 08-08-2019 11:09 AM

Quote:

Originally Posted by Gt86Force (Post 3244636)
Go with stock rotors, steel brake lines, RBF600 (or similar) and Ferodo DS2500.
I've tracked a lot with that combo without issues, and stil daily driving the car.

I started with Ferodo DS2500, and they are just not suitable for any serious track use. They are fine for a beginner who is doing occasional track days and primarily daily driving, they are not suitable for serious track use at all.

I don't want to be that guy, but based on some of the advice in this thread, it's really important to note that for critical safety systems you should be careful about making recommendations. Just because something worked for you does not mean it will work well for everyone, and most importantly, faster drivers are harder on critical subsystems. If you are finding the DS2500 (and RBF600 for that matter) sufficient on track, no offense but you're a slow driver. Neither of these are suitable for hard use.

I think it was Terry Fair that made the point that you should compare your laptimes on your preferred local track to what Spec Miata folks are doing on average. If you aren't beating the Spec Miata average lap time, you're slow and your experiences may not be suitable to extrapolate to someone else who is using their car harder than you are.

CSG Mike 08-08-2019 12:35 PM

Quote:

Originally Posted by Tristor (Post 3245768)
I started with Ferodo DS2500, and they are just not suitable for any serious track use. They are fine for a beginner who is doing occasional track days and primarily daily driving, they are not suitable for serious track use at all.

I don't want to be that guy, but based on some of the advice in this thread, it's really important to note that for critical safety systems you should be careful about making recommendations. Just because something worked for you does not mean it will work well for everyone, and most importantly, faster drivers are harder on critical subsystems. If you are finding the DS2500 (and RBF600 for that matter) sufficient on track, no offense but you're a slow driver. Neither of these are suitable for hard use.

I think it was Terry Fair that made the point that you should compare your laptimes on your preferred local track to what Spec Miata folks are doing on average. If you aren't beating the Spec Miata average lap time, you're slow and your experiences may not be suitable to extrapolate to someone else who is using their car harder than you are.

The quick 86CUP stock class guys beat the Spec Miata lap records, as a reference point.

Gt86Force 08-13-2019 12:36 PM

Quote:

Originally Posted by Tristor (Post 3245768)
I started with Ferodo DS2500, and they are just not suitable for any serious track use. They are fine for a beginner who is doing occasional track days and primarily daily driving, they are not suitable for serious track use at all.

I don't want to be that guy, but based on some of the advice in this thread, it's really important to note that for critical safety systems you should be careful about making recommendations. Just because something worked for you does not mean it will work well for everyone, and most importantly, faster drivers are harder on critical subsystems. If you are finding the DS2500 (and RBF600 for that matter) sufficient on track, no offense but you're a slow driver. Neither of these are suitable for hard use.

I think it was Terry Fair that made the point that you should compare your laptimes on your preferred local track to what Spec Miata folks are doing on average. If you aren't beating the Spec Miata average lap time, you're slow and your experiences may not be suitable to extrapolate to someone else who is using their car harder than you are.

I agree, but I think also the OP is a starter (not recognizing brake fade is a beggineer mistake). BTW is not criticising, we all have been/are there! You need seat time and mistakes to learn!

The great thing with this platform is that you can start to approach the track with the car almost stock. Pads, oil, brake lines and tires and you are good to go IMHO.
If you can pace yourself, this car gives you the opportunity to learn a lot because is simple and really communicative. If you start with slicks, bbk, more power ecc. ecc. ignoring the fact that it may be dangerous, a lot of the root causes of your mistakes are not clear. (wrong braking technique for example).

I've started with that config, and upgraded when it stopped being enough. Now i'm running 265,ap racing (made by a company named essex, btw if you don't know them check out their website!! great products), more power, cooling ecc. ecc. It is a journey as it should be for every car you track independently of your experience.

And yes I'm slow driver, no offense! taken :thumbsup:
I still pay for my track days, cars, mods, tires and gas. When you are fast usually you are getting payed.

biggie 09-13-2019 06:49 AM

Short review of the new setup (Stoptech slotted rotors, Carbotech XP10 pads - front only - Stoptech brake lines all around and same Castrol SRF).

During the pad's bed-in period the squealing was unbearable. This process took quite a long time, up to 600 miles of mixed driving (20% city, the rest up in the mountains).
Now, after more than 1k miles it seems to be a bit less noisy and I hope that's the case because they are bedded in properly and not because the outside temps have dropped in the last 2 weeks.
Up the mountains they behave great, lot's more feedback, no issues whatsoever.

On the track however there's an obvious tendency on straight hard braking for the back to slide around quite a lot. This was not the case before and my guess is because of the different pads in the back (yellowstuff). Also, the difference in feedback is not obvious on hard braking (and this is the case on most corners). Maybe there should not be any difference or I'm still to new in this and unable to see it, or maybe I did not pushed them hard enough for the difference to became obvious. Lap times are on par with those from my last trackday so I'm a bit disappointed. Ar least I'm more confident in my brakes.

I'll keep the pads for now, but I think I'll try something different next time (mostly because of the noise). Next on my list were Club Racer and DTC-60, does anyone know how these compare (noise wise) with XP10?

P.S. worth mentioning is that this time I did some cooling laps every 5 minutes or so :)

new2subaru 09-13-2019 08:09 AM

Quote:

Originally Posted by biggie (Post 3256980)
Short review of the new setup (Stoptech slotted rotors, Carbotech XP10 pads - front only - Stoptech brake lines all around and same Castrol SRF).

During the pad's bed-in period the squealing was unbearable. This process took quite a long time, up to 600 miles of mixed driving (20% city, the rest up in the mountains).
Now, after more than 1k miles it seems to be a bit less noisy and I hope that's the case because they are bedded in properly and not because the outside temps have dropped in the last 2 weeks.
Up the mountains they behave great, lot's more feedback, no issues whatsoever.

On the track however there's an obvious tendency on straight hard braking for the back to slide around quite a lot. This was not the case before and my guess is because of the different pads in the back (yellowstuff). Also, the difference in feedback is not obvious on hard braking (and this is the case on most corners). Maybe there should not be any difference or I'm still to new in this and unable to see it, or maybe I did not pushed them hard enough for the difference to became obvious. Lap times are on par with those from my last trackday so I'm a bit disappointed. Ar least I'm more confident in my brakes.

I'll keep the pads for now, but I think I'll try something different next time (mostly because of the noise). Next on my list were Club Racer and DTC-60, does anyone know how these compare (noise wise) with XP10?

P.S. worth mentioning is that this time I did some cooling laps every 5 minutes or so :)

It doesn’t sound like you’re bedding the pads properly prior to using them. Driving 600 miles has nothing to do with it.

Look up bedding track brake pads.

churchx 09-13-2019 08:50 AM

+1. Track pads have high working temps. Normal daily driving rarely heat them up to those. If anything, one of main reasons for many track pads to squeal is for daily driving light braking pattern to wear down bedded layer from rotors in few days, thus asking for rebedding from time to time if one chooses using track pads all the time.

norcalpb 09-13-2019 01:28 PM

Normal street pads you would drive a ton of miles and they naturally bed themselves.

Track pads you need to be quite the lunatic but it only takes 10 min.

Accelerate to 60mph in 2nd gear. Slam on the brakes with 70% force until you slow down to 10mph. Do this 5 times in a row. Yes you will look like a crazy person so do this somewhere private. DO NOT come to a full stop as this may damage your rotors. Make a U turn on the road you were on and do the same thing but at 100% braking force (do not engage ABS as this’ll fuck it up too). Once you’ve done your 5 100% braking force 60-10mph brake runs drive around for 20 min (no full stops) to let the brakes properly cool.

I say 5 times as a general guideline as this depends entirely on your brake compound and tires. 200tw tires get the brakes to proper temp quickly when braking hard, but it may take more than 5 brake runs with a true track pad.

I like to do it until I can smell the brakes. Sometimes you can see sparks shoot out which is normal.

churchx 09-13-2019 01:40 PM

And now some eye candy instead of text :)
[ame]https://www.youtube.com/watch?v=pdPX6rzuINc[/ame]

norcalpb 09-13-2019 02:01 PM

I find it hilarious that race tracks say absolutely no bedding on track. So where do they expect you to do it without the risk of getting pulled over??

NoHaveMSG 09-13-2019 02:10 PM

Quote:

Originally Posted by norcalpb (Post 3257055)
I find it hilarious that race tracks say absolutely no bedding on track. So where do they expect you to do it without the risk of getting pulled over??

I have some pretty good roads out here for it. Of course we are not nearly as populated.

churchx 09-13-2019 02:15 PM

BTW, regarding brake bedding topic - why not keep pressing accelerator simultaneously while braking? In most cars brake torque is way more then engine torque, and it will still slow down, also engine torque = less chance to lock up brakes, shouldn't it ease putting same amount of heat vs just braking in fewer iterations of slowdowns and from lesser top speeds? Or how about floored accel pedal at low gear to maximize torque, and mid-brake just about for constant speed .. shouldn't it also continuously just build up more and more heat in single cycle? Anybody know of possible illeffects of using engine torque during bedding, why such way is not mentioned in most bedding instructions?

wparsons 09-13-2019 02:39 PM

Quote:

Originally Posted by norcalpb (Post 3257055)
I find it hilarious that race tracks say absolutely no bedding on track.


Unpredictable braking down to slow speeds will cause a crash in a HUGE hurry on a track.



Quote:

Originally Posted by norcalpb (Post 3257055)
So where do they expect you to do it without the risk of getting pulled over??


In the paddock, or on a brake dyno (you can buy pre-bedded rotors/pads from race shops).

strat61caster 09-13-2019 02:41 PM

no need to overstress the drivetrain since brake pads for racecars go on racecars that may have powertrains that aren't super durable

Also many modern ECU's cut power when brake and gas are applied simultaneously due to the Prius accidents like 15 years ago, it wouldn't be possible on a lot cars.

Also @biggie get XP10's for the rear as well, it will totally fix the instability, and agreed that you didn't properly bed them in until you started doing laps. Yes they don't feel radically different but you should be able to use them harder and longer than what you had before.

NoHaveMSG 09-13-2019 02:56 PM

Quote:

Originally Posted by churchx (Post 3257061)
BTW, regarding brake bedding topic - why not keep pressing accelerator simultaneously while braking? In most cars brake torque is way more then engine torque, and it will still slow down, also engine torque = less chance to lock up brakes, shouldn't it ease putting same amount of heat vs just braking in fewer iterations of slowdowns and from lesser top speeds? Or how about floored accel pedal at low gear to maximize torque, and mid-brake just about for constant speed .. shouldn't it also continuously just build up more and more heat in single cycle? Anybody know of possible illeffects of using engine torque during bedding, why such way is not mentioned in most bedding instructions?

All bedding instructions I have read say not to do that. No reason is given though.

RFB 09-13-2019 04:29 PM

Quote:

Originally Posted by NoHaveMSG (Post 3257078)
All bedding instructions I have read say not to do that. No reason is given though.

Korporate Kash k-ching probably, doing it their way probably wears out the pads faster breaking them in their way. More money for Kommie Korporate swine.
;):laughabove:;)

NoHaveMSG 09-13-2019 04:36 PM

Quote:

Originally Posted by RFB (Post 3257102)
Korporate Kash k-ching probably, doing it their way probably wears out the pads faster breaking them in their way. More money for Kommie Korporate swine.
;):laughabove:;)

That makes no sense but okay.

If I had to guess, dragging the brakes may create too much heat in the rotors to develop a transfer layer, but I dunno :iono:

DarkSunrise 09-13-2019 06:02 PM

Quote:

Originally Posted by biggie (Post 3256980)
Short review of the new setup (Stoptech slotted rotors, Carbotech XP10 pads - front only - Stoptech brake lines all around and same Castrol SRF).

During the pad's bed-in period the squealing was unbearable. This process took quite a long time, up to 600 miles of mixed driving (20% city, the rest up in the mountains).
Now, after more than 1k miles it seems to be a bit less noisy and I hope that's the case because they are bedded in properly and not because the outside temps have dropped in the last 2 weeks.
Up the mountains they behave great, lot's more feedback, no issues whatsoever.

On the track however there's an obvious tendency on straight hard braking for the back to slide around quite a lot. This was not the case before and my guess is because of the different pads in the back (yellowstuff). Also, the difference in feedback is not obvious on hard braking (and this is the case on most corners). Maybe there should not be any difference or I'm still to new in this and unable to see it, or maybe I did not pushed them hard enough for the difference to became obvious. Lap times are on par with those from my last trackday so I'm a bit disappointed. Ar least I'm more confident in my brakes.

I'll keep the pads for now, but I think I'll try something different next time (mostly because of the noise). Next on my list were Club Racer and DTC-60, does anyone know how these compare (noise wise) with XP10?

P.S. worth mentioning is that this time I did some cooling laps every 5 minutes or so :)

When I had xp10's, I only remember getting squeal when the transfer layer had worn off. Try re-bedding them. What I did was 60-5 mph x 10, threshold braking, no ABS. Helps to be on your track tires. Can usually smell the brake pads a bit afterwards.

As strat mentioned, the cause of the instability is probably the difference in pad friction coefficient between the xp10's and ebc yellows. Try matching pads front to rear.

new2subaru 09-13-2019 06:13 PM

You can do it on rural roads if careful.

100-10kmph 10 times over like stated in the post above. I do it all the time prior to track. Do it at your own risk. The layer wears off on the way home...

I would never attempt it on track unless is was closed lol

biggie 09-14-2019 01:56 PM

2 Attachment(s)
The only thing I did to bed-in the pads was to avoid hard braking (with ABS) during the first 200km of city driving. It seems I keep doing stupid things :(

After that I left for the mountains and I really pushed them hard the whole trip. Then I hit the track and the rest you know.

I have a 80km drive to the nearest track with about 40km of highway in the middle. I'm going to try re-bedding them on the highway on my way to the track next saturday.

Meanwhile, here are some pictures of the rotors, looks good to me and the surface feels very smooth and plain.

Evan55 09-22-2019 12:22 AM

Quote:

Originally Posted by CSG Mike (Post 3245804)
The quick 86CUP stock class guys beat the Spec Miata lap records, as a reference point.


In my division, SM times are competitive with T4, so that really didnt sound right to me.
So I looked it up:

Sonoma
SM: 1:54.9
86cup stock: 2:00.8

Laguna Seca
SM: 1:45.5
86cup stock: 1:48.6

Willow Springs
SM: 1:36.1 (2016)
86 cup stock: 138.6


Not that those results are anything to be ashamed of for a car on street tires, SMs are actually very fast.
It takes 86cup modified class to beat SM records at Laguna and Sonoma.

strat61caster 09-22-2019 03:24 AM

Hard to beat a Miata on Hoosiers with street tires and an extra 500 lbs, SM records should drop next year as they start using the Penskes, 86cup will drop too as people get more experience building to the ruleset, not a great comparo since fast tires get punished so hard, stick R7s on an 86cup Stock class car and I would bet on the 86.

CSG Mike 09-23-2019 10:46 PM

Quote:

Originally Posted by Evan55 (Post 3259871)
In my division, SM times are competitive with T4, so that really didnt sound right to me.
So I looked it up:

Sonoma
SM: 1:54.9
86cup stock: 2:00.8

Laguna Seca
SM: 1:45.5
86cup stock: 1:48.6

Willow Springs
SM: 1:36.1 (2016)
86 cup stock: 138.6


Not that those results are anything to be ashamed of for a car on street tires, SMs are actually very fast.
It takes 86cup modified class to beat SM records at Laguna and Sonoma.

"stock class" doesn't run "Street tires" in the sense of 200TW tires. 200TW tires are banned in 86CUP stock class. These are 220TW tires, e.g. OEM tires, or SX2!

That being said, if we have the fast guys run stock class cars for times, I can 100% assure you the SM times would be beat. These "fast guys" would be T25 winners, pros, etc. They simply choose not to be big fish in small pond, at what is essentially a friendly competition.


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