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Did another track session, brakes not happy... (pics inside)

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Old Sep 15, 2008 | 03:23 PM
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Default Did another track session, brakes not happy... (pics inside)

Had a track session today, first time in at least 6 months The rollbar, harness and seat make all the difference in actually staying in the right spot without holding yourself in the seat

Session was only about 20 minutes and the track is not that demanding on brakes (only 3 hard braking points from 90-100 to 30-40) but still managed to fade them badly. After the cooling down run around the parking lot and stopping, I noticed the brake pedal going to the floor as easy as the throttle pedal. Took zero effort to push the pedal al the way to the floor. I noticed the right front brake caliper burned of most of the paint and the rotor does not look healthy either. The rest of the calipers and rotors still look as good as they did before

The right front caliper:
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The left front caliper:
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What I'm planning on now is stainless braided lines, fluid change to good DOT 4 fluid (ATE super blue is on sale here now) and decent pads, probably Axxis Ultimates or Ferodo 2500's. I don't want to change pads every month for a 20 to 40 minute track session.

Do I need proper ducting (have R-pack lip and splitter) or just learn how to brake properly?

The car as it looks right now:
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Last edited by Oscar; Sep 21, 2008 at 12:36 PM.
Old Sep 15, 2008 | 03:36 PM
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How was Zandvoort for you today?
You may have a dragging caliper since only one front is overheating?
What seats did you get BTW?
Old Sep 15, 2008 | 03:43 PM
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Zandvoort was excellent, dry and slightly overcast and some wind, but very nice overall. The sessions were not crowded at all which is very good aswell.
Not sure about the dragging caliper. Shouldn't I have noticed that before? The paint only came of after this sessios and the car never pulls to the right or makes funny sounds at the brakes. I'll check them soon tho. The drive home (20 minutes) was ok, just needed some more brake pressure to actually stop

I have one Corbeau Forza seat btw.
Old Sep 15, 2008 | 03:44 PM
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what pads? what power level?
Old Sep 15, 2008 | 03:48 PM
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My bad, pads are stock Mazda pads. Fluid got changed a few months ago. Driving around at a whopping 127 crank HP (lost the dyno plot showing rwhp..)
Old Sep 15, 2008 | 05:29 PM
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You still have rust in the grooves after the session? Then you're not getting full contact between the pad and the rotor. Using "all" of the braking power available should seat the pads to the rotor surface in a short time.

There is a technique to braking- it has a "power curve" similar to that of a big turbo on a small engine. That curve allows a smooth transfer of load to the front end. As load moves forward, grip goes up and braking (pedal) force increases.

I raced with a guy who ran Mazda stock pads and never had problems, though they were only good for the weekend which was about 2-3 hours of track time.
Old Sep 15, 2008 | 06:46 PM
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i vote caliper sticking. i actually have my driver caliper draging right now, and it doesn't pull or anything like that either.
Old Sep 15, 2008 | 07:05 PM
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Originally Posted by m2cupcar
You still have rust in the grooves after the session? Then you're not getting full contact between the pad and the rotor. Using "all" of the braking power available should seat the pads to the rotor surface in a short time.

There is a technique to braking- it has a "power curve" similar to that of a big turbo on a small engine. That curve allows a smooth transfer of load to the front end. As load moves forward, grip goes up and braking (pedal) force increases.

I raced with a guy who ran Mazda stock pads and never had problems, though they were only good for the weekend which was about 2-3 hours of track time.
the rust in the grooves was not there before the session tho. Could a sticking caliper cause uneven contact between pad and rotor? Shouldn't I have noticed this other than visually? (no pulling to one side for instance..)
Old Sep 15, 2008 | 07:24 PM
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I'm very surprised there is still rust on the caliper after a track day.

Something not right there imo. I would go with new rotors, pads, and stainless brake lines and see if that fixes it.
Old Sep 15, 2008 | 08:38 PM
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Rebuild that caliper first.

Makes sense that you didn't notice it, since you usually don't drive enough to (almost) cook brake parts.
Old Sep 15, 2008 | 10:29 PM
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you won't like axxis ultimates... I've been running them for about 2 years purely as a street pad and they aren't good enough. On the track they'd probably get your killed.
Old Sep 15, 2008 | 10:50 PM
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Originally Posted by Arkmage
you won't like axxis ultimates... I've been running them for about 2 years purely as a street pad and they aren't good enough. On the track they'd probably get your killed.
i'm on axxis ultimates, on the street tires are the limiting factor way before the pads at any speed
Old Sep 16, 2008 | 01:37 AM
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It probably is not rust. Look at his wheel, it's kinda dirty. You probably went through a small pool filled with gravel with that wheel. The other wheel is clean.

This does show grooves in the disc though. I'd rebuild both front calipers and get new discs + pads up front.
Old Sep 16, 2008 | 09:37 AM
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So I ordered some pads. Decided to get some Ferodo DS2500s all around. Both front calipers will be rebuilt. Need to take of the rotors to check them, but I'll probably replace them too. Fluid will be done at the same time, aswell as stainless lines.

I thought that, even with a complete stock brake system, you should be able to lock the fronts on the track when braking hard. Never managed to even tho I brake plenty hard
Old Sep 16, 2008 | 09:39 AM
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Good choice. Let us know if it works for you. Where did you order them and at what price?
Old Sep 16, 2008 | 09:44 AM
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Getting them through a local race shop here. Price is quite decent. They have a lead time of 2-3 weeks though. Gives me enough time to get things done at least..
Old Sep 16, 2008 | 09:50 PM
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Originally Posted by Mach929
i'm on axxis ultimates, on the street tires are the limiting factor way before the pads at any speed
they stop fine... the first 2-3 times. they tend to fade like a mother ******.
Old Sep 16, 2008 | 10:06 PM
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I was thinking that it was a sticking caliper, but the rusted rotor grooves are throwing me off. I think the "rust" might actually be brake dust bedded in the rotor. I could be wrong, though.
Pedal feel is gone because you boiled your brake fluid. Been there, done that.
Your new list of brake upgrades is good. I run Hawk Blues on the track w/ r compounds now because I boiled my motul with hawk hp+ pads and race tires.

Let us know your thoughts after you track it with the new equipment.
Old Sep 20, 2008 | 02:49 PM
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Stainless lines ordered. Pads are on backorder and should get here in less than 2 weeks. Still undecided about rotors. Fluid will be ATE super blue.
I think that should hold up decently on the track for the time being
Old Sep 21, 2008 | 12:35 PM
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found some pics, not that y'all care but still
Attached Thumbnails Did another track session, brakes not happy... (pics inside)-m0812-0244.jpg   Did another track session, brakes not happy... (pics inside)-m0812-0310.jpg  



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