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-   -   Brake issues on the track (https://www.ft86club.com/forums/showthread.php?t=45347)

Mike @ MRP 08-27-2013 03:27 PM

Brake issues on the track
 
Took the FRS to lime rock when I first got it and overheated the brakes 2 laps in. Wasn't too smart knowing the stock pads would do this anyway. So since then I've changed a bunch of things: steel braided lines, ate blue stuff fluid, centric blanks and carobtech p10 pads. Hoping this would do the job but mid way into my first session this passed weekend, same thing happen. Obviously not as bad but still started getting that soft pedal feel and bad brake fad.

I don't want to have to do a big brake kit since they're a ton of money. Any suggestions on what else to get around this. Maybe brake ducts could help a little?

Mod list: intake, front pipe, cat back, ecutek tuned on e85 by Visconti.

OrbitalEllipses 08-27-2013 03:36 PM

DOT unapproved brake fluid, yo.

forwallblakmail 08-27-2013 03:38 PM

Never ran at Lime Rock, but I tracked at PittRace this weekend which is decently hard on brakes. No fade in all 4 20 minutes sessions. I run Carbotech XP12's F/R and Motul RBF 600 fluid.

Mods are RCE Tarmac Springs, Koni yellows, front bar, 245 BFG rivals.

What tires are you running?

CSG Mike 08-27-2013 04:01 PM

Quote:

Originally Posted by Mike @ MRP (Post 1170612)
Took the FRS to lime rock when I first got it and overheated the brakes 2 laps in. Wasn't too smart knowing the stock pads would do this anyway. So since then I've changed a bunch of things: steel braided lines, ate blue stuff fluid, centric blanks and carobtech p10 pads. Hoping this would do the job but mid way into my first session this passed weekend, same thing happen. Obviously not as bad but still started getting that soft pedal feel and bad brake fad.

I don't want to have to do a big brake kit since they're a ton of money. Any suggestions on what else to get around this. Maybe brake ducts could help a little?

Mod list: intake, front pipe, cat back, ecutek tuned on e85 by Visconti.

Did the pedal get mushy, or the car just stop braking?

What kind of tires are you on? (Make, model, and size) Are you running XP10 front/rear?

XP10 is great for intermediate level guys, but if you're quick, XP12 is the way to go (assuming you want to stick to Carbotech). If you're in a hurry, I believe we have it in stock.


It's very possible that they were bedding the 1st session; did the brakes improve later? ATE generally is not suited for quicker drivers. I'd recommend trying Motul RBF600. If that doesn't work, step up to Project Mu. If that doesn't work, then Torque RT700.

This isn't a FR-S/BRZ, but this picture is from the past weekend, with Project Mu 999, and Torque RT700. One of the rotors cracked during cooldown, but the brake fluid didn't get mushy, and the pads never faded. https://fbcdn-sphotos-c-a.akamaihd.n...61617586_o.jpg

7thgear 08-27-2013 04:03 PM

did you bed the pads/rotors in?

subaruferrucci 08-27-2013 05:48 PM

almost sounds like you are not applying your brakes aggressively enough. when you are on the track you should be braking much harder. When you drag the brake like you are rolling up to a stop sign looking for the smooth stop you will boil your fluid really fast

ATL BRZ 08-27-2013 05:59 PM

Proper bleeding of the system as well as proper bedding in of the pads is important, but the stock style rotors need better cooling.

Check out my build thread for my solution. I installed the Touge Factory brake cooling kit which features ducts, hoses, and a proper backing plate that helped tremendously at the track. I can drive 9 or 10/10ths now on track and the brakes are consistent into every corner.

Also get a master cylinder brace, that helps a lot with solidifying the pedal feel in threshold braking situations.

smbstyle 08-27-2013 06:22 PM

First off, let me get this one out of the way, I hate Carbotechs, and always had issues with them. Are the pads bedded properly? Carbotech has specific directions on properly bedding them.

I'll notice a "soft" pedal after a cool down lap going into a hard braking turn, as the pads have cooled down significantly, but usually 3 to 4 seconds in the bite gets progressively better.

Soft pedal sounds like a fluid issue. There could be air in the lines or you could be boiling the fluid, but I don't think Lime Rock is the kinda track that would boil fluid. I ran ATE at Sebring on all my cars without issue (CTS-V, Miata).

If the pedal feels still kinda firm, but theres no bite, pads could be glazed. Take them out, rub them against the concrete, and re-bed.

One thing that not a lot of people think of is pad knock-back, which I had an issue with on my Miata. It is when the lateral movements through the corners will push the pads out from the rotor surface, so when you go to the brakes, pedal goes to the floor for the initial pump, and is definitely a butt-clencher.

I do a light brake tap in the straights before the brake zone by habit after my Miata race car, so I wouldn't know if this car had that issue or not.

Mike @ MRP 08-28-2013 03:22 PM

Quote:

Originally Posted by forwallblakmail (Post 1170650)
Never ran at Lime Rock, but I tracked at PittRace this weekend which is decently hard on brakes. No fade in all 4 20 minutes sessions. I run Carbotech XP12's F/R and Motul RBF 600 fluid.

Mods are RCE Tarmac Springs, Koni yellows, front bar, 245 BFG rivals.

What tires are you running?

Sorry, forgot to mention wheel and tire combo. 17x8 kosei and Rivals 225 wide.

Mike @ MRP 08-28-2013 03:50 PM

Quote:

Originally Posted by CSG Mike (Post 1170711)
Did the pedal get mushy, or the car just stop braking?

What kind of tires are you on? (Make, model, and size) Are you running XP10 front/rear?

XP10 is great for intermediate level guys, but if you're quick, XP12 is the way to go (assuming you want to stick to Carbotech). If you're in a hurry, I believe we have it in stock.


It's very possible that they were bedding the 1st session; did the brakes improve later? ATE generally is not suited for quicker drivers. I'd recommend trying Motul RBF600. If that doesn't work, step up to Project Mu. If that doesn't work, then Torque RT700.

This isn't a FR-S/BRZ, but this picture is from the past weekend, with Project Mu 999, and Torque RT700. One of the rotors cracked during cooldown, but the brake fluid didn't get mushy, and the pads never faded. https://fbcdn-sphotos-c-a.akamaihd.n...61617586_o.jpg

I'm running the xp10 in the front and sad to say stock pads in the rear (yes I know dumb lol). I do consider myself to be quick on the track. Currently hold lap record at lime rock with my spec miata. I had the FRS clocked at 1:03.2 which I was very impressed with.

Going to order rear pads this week, do y recommend going with xp10 or xp8 for the rear. I just got the xp10 for the fronts so going to just burn them out and go with xp12s next time around. Only issue is the car is daily driven so I didn't want to go with such an aggressive pad.

As for brake fluid, I guess ate isn't cutting it for me. Going to switch over the motul this week. Running it at njmp next week which requires more use of brakes.

CSG Mike 08-28-2013 05:02 PM

Quote:

Originally Posted by Mike @ MRP (Post 1173525)
I'm running the xp10 in the front and sad to say stock pads in the rear (yes I know dumb lol). I do consider myself to be quick on the track. Currently hold lap record at lime rock with my spec miata. I had the FRS clocked at 1:03.2 which I was very impressed with.

Going to order rear pads this week, do y recommend going with xp10 or xp8 for the rear. I just got the xp10 for the fronts so going to just burn them out and go with xp12s next time around. Only issue is the car is daily driven so I didn't want to go with such an aggressive pad.

As for brake fluid, I guess ate isn't cutting it for me. Going to switch over the motul this week. Running it at njmp next week which requires more use of brakes.

We recommend square pads; that's where we had the best results with braking distances.

Yeah, you're quick. You're fading the XP10 fronts; I did some informal testing with just XP12 front/stock rear, and I was fading them after just a few hot laps, so a drive of your caliber has to be feeling the pain.

I suppose I should mention, brakes on this car wear much faster than on a Miata...

rice_classic 08-28-2013 05:08 PM

Do you know how to properly bed-in (or burnish) Carbotech's?

You have to brake from 60mph to 10mph 3 times on a summer day with the sun at the 4 O'clock position all while crossing all the fingers on both hands and praying to Vishnu with a memorized chant that will be provided by Carbotech.

What's wrong? Didn't cross all of your fingers? Well, UNEVEN TRANSFER LAYER FOR YOU!

http://3.bp.blogspot.com/-62mERgzUrZ...s_soupnazi.jpg

rice_classic 08-28-2013 05:11 PM

Quote:

Originally Posted by subaruferrucci (Post 1170963)
almost sounds like you are not applying your brakes aggressively enough. when you are on the track you should be braking much harder. When you drag the brake like you are rolling up to a stop sign looking for the smooth stop you will boil your fluid really fast

This is no joke.

When I was learning how to race, I was destroying my brakes. I was on them too early, too little and for too long and entering the corner too slow. Just a change in driving fixed it all.

Brake late, brake hard, carry more speed into corner. (But be safe!)

smbstyle 08-28-2013 05:37 PM

Quote:

Originally Posted by rice_classic (Post 1173741)
Do you know how to properly bed-in (or burnish) Carbotech's?

You have to brake from 60mph to 10mph 3 times on a summer day with the sun at the 4 O'clock position all while crossing all the fingers on both hands and praying to Vishnu with a memorized chant that will be provided by Carbotech.

What's wrong? Didn't cross all of your fingers? Well, UNEVEN TRANSFER LAYER FOR YOU!

http://3.bp.blogspot.com/-62mERgzUrZ...s_soupnazi.jpg

aint that the truth.

I think I went from 62mph to 11mph 3 times at 4:15 pm. probably I had all kinds of issues with the Carbotechs.

bolecailey 08-29-2013 04:44 AM

I am surprised no one reccommends Castrol SRF. I know it is expensive but it last much longer and requires less bleeding. I have never had good luck with ATE.

kask2_6.0 08-29-2013 08:17 AM

Quote:

Originally Posted by bolecailey (Post 1175225)
I am surprised no one reccommends Castrol SRF. I know it is expensive but it last much longer and requires less bleeding. I have never had good luck with ATE.

Just switched over to the SRF this past weekend. But I went that route because that was the cheapest in my situation.. FREE :party0030:

If you can spring for it Endless fluid is the best but not sure how it will react with the OE seals.

Guillaume 08-29-2013 08:41 AM

Quote:

Originally Posted by Mike @ MRP (Post 1173525)
Going to order rear pads this week, do y recommend going with xp10 or xp8 for the rear. I just got the xp10 for the fronts so going to just burn them out and go with xp12s next time around. Only issue is the car is daily driven so I didn't want to go with such an aggressive pad.

That's my exact setup, it is well balanced.

Regarding the XPs, you do know they need a special bedding procedure along with either new rotors or rotors that have been used with ceramic based pads, right? You shouldn't put Carbotech XPs on your rotors that have been used with the stock pads.

The car is also my DD, and except a slightly annoying noise at low speed and copious amount of (wheel friendly) dust, it is no problem. There is plenty of cold bite.

bolecailey 08-29-2013 11:00 PM

Quote:

Originally Posted by kask2_6.0 (Post 1175290)
Just switched over to the SRF this past weekend. But I went that route because that was the cheapest in my situation.. FREE :party0030:

If you can spring for it Endless fluid is the best but not sure how it will react with the OE seals.

SRF Has a higher wet boiling point than the endless, wet what is most important in my opinion. That is why people on SRF go whole track seasons without changing fluid or bleeding. Not that I would do it, but lots of SRF users go two seasons on it with only a bleed in between seasons.http://forums.rennlist.com/rennforum...strol-srf.html

kask2_6.0 08-29-2013 11:33 PM

Quote:

Originally Posted by bolecailey (Post 1177451)
SRF Has a higher wet boiling point than the endless, wet what is most important in my opinion. That is why people on SRF go whole track seasons without changing fluid or bleeding. Not that I would do it, but lots of SRF users go two seasons on it with only a bleed in between seasons.http://forums.rennlist.com/rennforum...strol-srf.html

That's pretty cool that the SRF can last that long and would definitely make it a good choice for most. However, the bulk modulus (resistance to compression) of the fluid is ultimately what will determine the performance and feel of the fluid. The endless has a higher bulk modulus than the SRF.

CSG Mike 08-29-2013 11:53 PM

Quote:

Originally Posted by bolecailey (Post 1175225)
I am surprised no one reccommends Castrol SRF. I know it is expensive but it last much longer and requires less bleeding. I have never had good luck with ATE.

Because it's silicon based, if it's the dot 5 one I'm thinking of... it doesn't do well with DOT 3/4 fluids and regular brake lines...

Quote:

Originally Posted by bolecailey (Post 1177451)
SRF Has a higher wet boiling point than the endless, wet what is most important in my opinion. That is why people on SRF go whole track seasons without changing fluid or bleeding. Not that I would do it, but lots of SRF users go two seasons on it with only a bleed in between seasons.http://forums.rennlist.com/rennforum...strol-srf.html

I hate to say it, but the majority of those guys have more dollars than talent.

CSG Mike 08-29-2013 11:55 PM

Quote:

Originally Posted by Guillaume (Post 1175302)
That's my exact setup, it is well balanced.

Regarding the XPs, you do know they need a special bedding procedure along with either new rotors or rotors that have been used with ceramic based pads, right? You shouldn't put Carbotech XPs on your rotors that have been used with the stock pads.

The car is also my DD, and except a slightly annoying noise at low speed and copious amount of (wheel friendly) dust, it is no problem. There is plenty of cold bite.

They'll bed just fine. Just expect to lose your first session to bedding, unless you can bed them, the night before.

Pabloc 08-30-2013 12:48 AM

Essex has nice instructions and theory on bedding new pads on their site. If I understand (disclaimer - not an engineering type), after bedding a pad and laying down a transfer layer, driving at street speeds erases the transfer layer through friction. A new transfer layer must be re-created by putting heat into the brakes through a bedding-in procedure. The cycle can be repeated. However, track pads will likely have undesirable characteristics when used on the street.

Do those procedures not apply with Carbotech pads? Why must the disc be resurfaced or new if stock pads have been used when changing to Carbotech pads?

Anyone know what happens if one DOESN'T follow their bedding procedures?

Will the world really end?

Dephective 08-30-2013 01:23 AM

Quote:

Originally Posted by Pabloc (Post 1177660)
Essex has nice instructions and theory on bedding new pads on their site. If I understand (disclaimer - not an engineering type), after bedding a pad and laying down a transfer layer, driving at street speeds erases the transfer layer through friction. A new transfer layer must be re-created by putting heat into the brakes through a bedding-in procedure. The cycle can be repeated. However, track pads will likely have undesirable characteristics when used on the street.

Do those procedures not apply with Carbotech pads? Why must the disc be resurfaced or new if stock pads have been used when changing to Carbotech pads?

Anyone know what happens if one DOESN'T follow their bedding procedures?

Will the world really end?

The reasoning being that the scoring on the rotors from the first set of pads will cause an uneven wearing of the pad, which will cause hot spots on the rotor, which in turn will wear both out faster and increase the risk of cracking discs. Not to mention non-optimal bedding.

I've always done it just to err on the side of caution, especially if you're going to be putting that much stress on the system. I'm no expert though.

bolecailey 08-30-2013 01:45 AM

Quote:

Originally Posted by CSG Mike (Post 1177558)
Because it's silicon based, if it's the dot 5 one I'm thinking of... it doesn't do well with DOT 3/4 fluids and regular brake lines...



I hate to say it, but the majority of those guys have more dollars than talent.


Lol Mike, I know that. I think anyone who is a decently fast driver knows what it is like to be held up by rich guys in there 100k+ cars. They just want to run flat out. Back when my dad used to take his formula continental to the Porsche club events in Corpus for practice, the 11th fastest time of one particular weekend was a guy in a race prepped dodge neon. He said that guy was consistently in the top 15.

Mike @ MRP 08-30-2013 02:45 AM

Quote:

Originally Posted by CSG Mike (Post 1173716)
We recommend square pads; that's where we had the best results with braking distances.

Yeah, you're quick. You're fading the XP10 fronts; I did some informal testing with just XP12 front/stock rear, and I was fading them after just a few hot laps, so a drive of your caliber has to be feeling the pain.

I suppose I should mention, brakes on this car wear much faster than on a Miata...

Lol I definitely learn the hard way that pads wear much quicker then they do on the Miata. I guess I'm trying to drive it too much like I do the miata too.

Mike @ MRP 08-30-2013 02:48 AM

Quote:

Originally Posted by Guillaume (Post 1175302)
That's my exact setup, it is well balanced.

Regarding the XPs, you do know they need a special bedding procedure along with either new rotors or rotors that have been used with ceramic based pads, right? You shouldn't put Carbotech XPs on your rotors that have been used with the stock pads.

The car is also my DD, and except a slightly annoying noise at low speed and copious amount of (wheel friendly) dust, it is no problem. There is plenty of cold bite.

The noise doesn't bother me on the street. I think it's kinda funny when you stop at lights and everyone around you gets annoyed lol

Mike @ MRP 08-30-2013 02:51 AM

[ame]http://youtu.be/cSqzS02fy3Q[/ame]

Video i put together from this passed week at Lime Rock.

Pabloc 08-30-2013 05:02 PM

Re bedding Carbotech pads/ need for new or resurfaced discs:

Quote:

Originally Posted by Dephective (Post 1177712)
The reasoning being that the scoring on the rotors from the first set of pads will cause an uneven wearing of the pad, which will cause hot spots on the rotor, which in turn will wear both out faster and increase the risk of cracking discs. Not to mention non-optimal bedding.

I've always done it just to err on the side of caution, especially if you're going to be putting that much stress on the system. I'm no expert though.



Are Carbotech pads unique, or is the theory the same for ALL pads?

Why don't other manufacturers recommend the same process?

Why, Why, Why?

CSG Mike 08-30-2013 05:03 PM

Quote:

Originally Posted by Pabloc (Post 1179270)
Re bedding Carbotech pads/ need for new or resurfaced discs:





Are Carbotech pads unique, or is the theory the same for ALL pads?

Why don't other manufacturers recommend the same process?

Why, Why, Why?

The theory is the same for all pads


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