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a few questions about BRAKES for fellow track guys

Old 05-17-14, 02:55 PM
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a few questions about BRAKES for fellow track guys

i just completed my 3rd event on my front track pads (and the rear pads have lasted 4 events)

the 3 track days were Road Atlanta (november), Putnam Park (april), and TGPR (may).

TGPR is a short track, and it was ~85*F outside, and this short track seemed to be the hardest on my brakes, maybe because of the lack of a long straight or long sweeper turns to allow the brakes to cool? i'm not sure, but i was not expecting the brakes to be gone after this event.

my car setup is as so:
~350whp single turbo setup, haltech, VMIC
18x9.5 RPF1 wheels with 265/35/18 RE11 tires
stock brakes with ate superblue fluid
Carbotech XP-10 pads (front)
Hawk HT-10 pads (rear)

anyway, my front pads are completely gone after 3 events, and the hawks on the rear have about 20-30% left, so it's time to replace all 4. was i wrong in expecting these to last 4 or 5 events?


1. how long are your pads lasting?

2. i'm also about to swap to some 285/30/18 toyo R888s that i'm getting at an extreme discount, so i'm wondering if that will warrant stepping up a notch in brake compound to XP-12s / PFC01 / DTC60/70?

3. how many of you run the same compound on all 4 corners? it makes sense to me to go this route, but i'm wondering if anyone has done any temp testing of the rear brakes (for comparison to the fronts) to see how hot they actually get. i know people typically go one step lighter on the rear compound, but i havent read anything REALLY confirming this is what we should be doing. any input on this would be beneficial, i'm sure.
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Old 05-17-14, 05:50 PM
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Stock pads generally last about that long. If you didn't crack any rotors, you are doing pretty good.

It will depend on what you want to do. I will say though... The R888 will put more heat in the brakes as you have increased mechanical grip and the ability to stop faster and will wear the pads faster than the RE11's. Your pad life will continue to decrease and you will see fade sooner. I would keep a spare set of rotors with you at the track as well as I wouldn't be surprised if you started to see some cracked rotors.

It will probably be fine to run the same compound on all 4 corners, but after a good bit of testing between me, Fritz, and Pete... the balance is better with a more aggressive front. This became glaringly apparent for me when I went full manual brake set up and tried DTC60's on all 4 corners. It took a lot of bias adjustment to keep the rears from locking up very quickly.

Obviously you may be just fine at your track event, but if not and you still don't want to move to larger brakes, it would be a good time to run either the R1 brake duct system or a custom application brake duct system to help get some more air in there.
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Old 05-17-14, 07:01 PM
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2. we found with more grip the brakes lasted longer, however, we're in a power limited car, so straight away speed didn't change with the new tires.

1. we were running PFC pads, and those lasted forever, they will run a whole 25 hour race, and or do a season and a half of racing. we recently put bigger brakes on with carbotech pads, so i don't know about wear yet. i can tell you the new bigger brakes are worse than the old small ones, so we have some unidentified problem.
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Old 05-17-14, 11:07 PM
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dalton, R1 ducts like these?



Mazda RX7 FD Brake Hose Adapter | RooDucts
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Old 05-18-14, 09:08 AM
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I am running PF97 all the way around on my ITS car. Added a bias valve in addition to the stock bias valve. Excellent brake performance and minimal wear. Note...twice my HP and a heavier car expect the brakes to go quicker.
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Old 05-18-14, 09:16 AM
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Jacob,
Those would be a good start though for a custom setup that would cool better than the stock ones. I can't for the life of me find the 93-95 brake ducts that came on the R1/R2, but here are the ones for the 99spec lip:
99 SPEC MAZDA (J-SPEC) RX7 Brake Ducts

For the price above, I'd make my own.
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Old 05-18-14, 07:37 PM
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dalton, i didnt think the 93-95s came with brake ducts at all. i thought that was only a 99+ thing.
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Old 05-18-14, 08:50 PM
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What Hawks do you have? I run DTS 60s and 30s on stock calipers and am very pleased with their prformance, but don't have enough runs to vouch for their longevity.
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Old 05-18-14, 09:06 PM
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I have an FC and run DTC 60s in front and 30s in the rear as well. Stock rear brakes, Mandeville front brake kit using 350z front rotors and stock calipers. 400 WHP and 255 NT01s all around.

I got about 6 track days out of the first set of front DTC 60s on stock front rotors. They were not to the point of fading, but the stock front rotors started developing large cracks, and I was flexing the calipers and getting tapered wear on the pads. Rears are wearing ok, I have about 8 track days on them, but they are getting a little to hot for my liking. I'm building brake cooling ducts for the front and back.

The temps on the front are not bad now with the 350z rotors. I'm using a fresh set of front calipers on the front and if the tapered wear continues, I'm going to go with wilwood front brake calipers.
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Old 05-18-14, 09:11 PM
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Jacob, you may be right. I was thinking that the 93-95's did but I'm way too drunk to taste this chicken. Gulden Drak is a [email protected]#cker. And by that, I mean awesome.
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Old 05-19-14, 12:02 AM
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Originally Posted by LargeOrangeFont View Post
I got about 6 track days out of the first set of front DTC 60s on stock front rotors. They were not to the point of fading, but the stock front rotors started developing large cracks, and I was flexing the calipers and getting tapered wear on the pads. Rears are wearing ok, I have about 8 track days on them, but they are getting a little to hot for my liking. I'm building brake cooling ducts for the front and back.

The temps on the front are not bad now with the 350z rotors. I'm using a fresh set of front calipers on the front and if the tapered wear continues, I'm going to go with wilwood front brake calipers.
I warped my stock rotors using the stock pads (may have sat on the brakes in an early track day). I now run the cryo-treated slotted Stoptech rotors with no probs
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Old 05-19-14, 12:21 AM
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The '93 R1 has brake ducts that snap into slots in the plastic under tray and connect the openings in the R1 lip to the wheel well area.

I think the confusion is because there are equivalent plastic pieces for the non R1s.

DUCT (R), AIR-BRAKE PIPE
43-63X
FD03-43-63XE (R1)
FD01-43-63XE (NORMAL)

DUCT (L), AIR-BRAKE PIPE
43-63X2
FD03-43-64XE (R1)
FD01-43-64XE (NORMAL)

They are about $117 each list or $70 w/ Mazdaspeed sponsorship.
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Old 05-19-14, 01:54 AM
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Originally Posted by TomU View Post
I warped my stock rotors using the stock pads (may have sat on the brakes in an early track day). I now run the cryo-treated slotted Stoptech rotors with no probs

Yea sounds like too much brake and cooking the stock pads. When you overheat stock pads they melt and put uneven deposits on the rotors. It feels like the rotors are warped after that.
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Old 05-19-14, 10:10 AM
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Tricky part with the ducting is not what attaches to the bumper/front, it's directing the air to the veins of the rotor. The front ducts are easy and there are several variations of NACA ducts you can use. For the rotor side, you'll likely have to be creative as I'm not sure there is anyone still making pre-fabbed backing plates to attach your hose.

Carbotech XP10 pads are decent, but they are not so great with the stickier tires. I would recommend going to their higher compounds for the track with stock calipers, even once you get ducting in place.
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Old 05-19-14, 02:42 PM
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Jacob, if your looking for backing plates let me know. I have the plate CAD design and have made a few of these now. If you need them I can get you a set.
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Old 05-19-14, 08:24 PM
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john, what do i need to do to get that CAD file from you?
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Old 05-19-14, 08:31 PM
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Originally Posted by Mahjik View Post
Tricky part with the ducting is not what attaches to the bumper/front, it's directing the air to the veins of the rotor. The front ducts are easy and there are several variations of NACA ducts you can use. For the rotor side, you'll likely have to be creative as I'm not sure there is anyone still making pre-fabbed backing plates to attach your hose.

Carbotech XP10 pads are decent, but they are not so great with the stickier tires. I would recommend going to their higher compounds for the track with stock calipers, even once you get ducting in place.


mahjik, thanks for the input.

which pads do you run? i have considered the XP12s and XP10s rear, but i'm not experienced enough to really notice the difference between pads yet, i don't think. i'm currently working on getting a race seat, as i've been flying all over the inside of the car at recent events, and i see that you've had some interesting posts on that topic as well.
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Old 05-19-14, 08:59 PM
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Originally Posted by jacobcartmill View Post
mahjik, thanks for the input.

which pads do you run? i have considered the XP12s and XP10s rear, but i'm not experienced enough to really notice the difference between pads yet, i don't think. i'm currently working on getting a race seat, as i've been flying all over the inside of the car at recent events, and i see that you've had some interesting posts on that topic as well.
Hands down best brakes for stock setup is hawk blue front and rear IF you have ABS and don't align with rear toe out. If you like rear toe out and or don't have ABS go with blue front and black rear. I like 1/16 total toe front and a little to zero in the rear and I also like the stock ABS which works great. I found DTC 60s crack rotors as do most of the high torque ceramic type pads, better to eat metal than heat metal/crack rotors.

Use only oem rotors

350 is way too much power for stock brakes and sh#tty rubber PERIOD. I have a nice like new sakebomb kit and buy some damn hoos hoos or lower the boost hehe, PM if you need some brakes

Hard to believe anyone is using less brake with a sticky tires but it's likely because it's a low power car that can't out run it's shadow/get out of the corner and the braking distance is shorter/entry speed is faster.

PS I also have a decent race seat that came out of Kyle's car along with a nice pair of momos, pm if interested in those as well.

PSS Have been running hawk blue on the back of my track car for years with great results. Every time I try something else it f#cks up the rotors.
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Old 05-19-14, 09:24 PM
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I like the Hawk DTC60s. Easier to drive than the blues and blacks in my opinion. remember that brake preference is going to be driver dependent.
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Old 05-19-14, 09:37 PM
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unfortunately with my current turbo setup i can't run less than ~10-11psi with my borg warner setup, which is still ~320-330whp :/


fritz, which seat came out of kyle's car? i'm currently checking out a Cobra Suzuka Pro seat on ebay for $450, and a local guy is selling a nice Sparco EVO (with a new cover) for $500.

i sat in a nice porsche today that had a leather wrapped Recaro SPG and now i want one of those.
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Old 05-19-14, 09:39 PM
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Originally Posted by jacobcartmill View Post
mahjik, thanks for the input.

which pads do you run? i have considered the XP12s and XP10s rear, but i'm not experienced enough to really notice the difference between pads yet, i don't think. i'm currently working on getting a race seat, as i've been flying all over the inside of the car at recent events, and i see that you've had some interesting posts on that topic as well.
Unfortunately, I no longer have my RX7 but I used to run N-Tech pads. I had bought several pairs before Nick stopped making them. I was going to move to the Carbotech pads XP16F/XP12R. I had run Carbotechs on my M3 for a while and still have a set left (in case I want to run some laps with it). It appears they are no longer doing the XP16's (next step is XP20), but XP12/10 would be a good setup until you get to the real sticky tires. For my Honda, I'm using Cobalt Friction pads but they are a little pricey.
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Old 05-19-14, 09:53 PM
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Originally Posted by jacobcartmill View Post
fritz, which seat came out of kyle's car?
Momo Start, pictured above.
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Old 05-19-14, 10:10 PM
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Originally Posted by Mahjik View Post




Momo Start, pictured above.
Thanks for the pic

Will sell cheap to anyone who wants it

Originally Posted by jacobcartmill View Post
unfortunately with my current turbo setup i can't run less than ~10-11psi with my borg warner setup, which is still ~320-330whp :/


fritz, which seat came out of kyle's car? i'm currently checking out a Cobra Suzuka Pro seat on ebay for $450, and a local guy is selling a nice Sparco EVO (with a new cover) for $500.

i sat in a nice porsche today that had a leather wrapped Recaro SPG and now i want one of those.
Jacob,
How big are you. I'm 5.9 150 and the sparco fits me great.

One thing to think about is safety and the seat is a really big part of that so you may want to just bite the bullet and get a race tech halo with hahns etc.....
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Old 05-19-14, 10:49 PM
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fritz, i am 5'10 ~140lbs of solid steel.

i think i am going to get this sparco EVO seat unless a better deal pops up. i have to unload my stock black leather FD seats first though :/ then i have to make a harness bar or a new solid rear strut tower bar. then buy harnesses... it never gets cheaper!


but i need to be PLANTED while i'm driving. i was flying all over the inside of the FD at my last event and my back and shoulders were hurting noticeably about halfway through the day.
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Old 05-20-14, 08:21 AM
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The Sparco Evo would be similar to the Momo Start. I'll bet Fritz will give you a better deal on the Momo than you'll get on the Sparco. The Momo was practically new when I sold the car to Fritz. I had a few track weekends with it and none of them during inclement weather.


Do you already have a rollbar? The other thing, I'm going to add to Fritz's comment about a halo seat. If you drive the car on the street still, do not get a halo seat. You won't be able to use the stock seat belts with it, and once you are strapped in with a harness, you cannot see well enough to the side with a halo seat for street driving. If the car is a pure track only car, a halo seat + roll protection + HANs + 5/6 point harness will give you great driver protection.
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