When I loaded the car up on the truck after the track day at Collie Denver and I were looking at the brakes on my car. Fair to say they are stuffed.

To be fair the pedal still feels fine and there was no fade or mushy pedal...however look at the photo below.

Car is a MY99 STI type RA (read no ABS) with autronics and an exhaust.

Rotors are DBA 5000 and Pads are Ferodo FS3000.

Since installation car has done the following

2x Days @ wanneroo
1x Days @ collie
1x Afternoon @ Belmont
4x Mornings @ AHG

Car does not get driven on the road. I.e. trucked to and from events.

Fair to say total mileage somewhere around 500km's.







You can see how some of the metal has melted and started to fill the grooves.

You can also see the colour changing paint has all but gone.

Out of interest does anyone know at what temperature the paint is meant to change.

Logic is that this is a little excessive.

Considering that Rotors (hats are reusable) and pads are around $1k a pop I think I will fit a hydraulic handbrake and then fit the front rotors on the back and buy something substantial for the front. It will pay off in the long run.

In the mean time I will take the rotor gaurds off the back of the rotors to try and let a bit more cooling in.

Cheers

Brendon

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Losing is worse than death. You have to live with losing....

The grooves are definately interesting to me. However, I think it may come down to these 3 things:

1). The type of pads- 3000's, while effective at higher temps really are aggressive on these types of rotors
2). Your braking style while doing multi-lap events (like Collie/ Wanneroo etc)- eg aggression!
3). An absence of effective brake ducting...

I run DBA5000's also, but have been using DS2500's etc. While I get some minor grooving and heat spots, after a multilap event this has generally been remedied by giving them a light scrub with a course wet n dry afterwards... I have also used brake ducting which comes in through the old fog lamp holes and ends up ramming air straight into the middle of the rotors. This makes a substantial difference when doing multilap stuff! (Heat is always the enemy with braking etc).

As for your slots... I reckon it's just a case of them getting low enough to start grinding away the grooves. I know Al and my own rotors are starting to do the same mate! Either that, or if they are still thick enough it'll be the sheer force of the DS3000 compound and the unequal distribution of pressure in the WRX 4pots.
(Ever noticed AP and Alcon designs have larger to smaller pistons in the caliper block? This is to prevent this uneven pad wear etc).

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"...even my Grandma can drive fast in a straight line"

From dba.com.au

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Does the heat paint return to its original colour?

The thermo graphic heat paint used in DBA 4000 and DBA 5000 series disc rotors has been developed to measure the actual bulk temperature of the disc when operating at the most extreme condition.

This peak condition is reached when the vehicle is in full motion with the brakes engaged. To enable an accurate measurement to be recorded, it is essential that the heat monitoring paint makes a permanent change at this critical point in braking.

If the paint were to return to its original colour as it cooled you would not achieve a true indication of the peak temperature as the disc can reduce in temperature by more than one hundred degrees Celsius before you have time to stop and check the reading.

The three paint stripes on these DBA performance rotors are;

Green 458˚C (856˚F) Changes to white
Orange 550˚C (1022˚F) Changes to yellow
Red 630˚C (1166˚F) Changes to white

In order for this colour change to occur, the disc rotor mass must reach the relevant bulk temperature for 10 minutes. This ensures that the colour change does occur from the much higher surface temperatures which do not penetrate through the disc material and affect its mechanical properties.
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The ideal temperature condition for high performance brake pads and rotors is between 450˚C and 550˚C which is when the peak friction condition is achieved. This can be verified when the Green paint changes to white and the Orange paint has not changed or minimal change occurs on the outer edges.

If your driving conditions force the Orange paint to change to yellow then you should consider more a specialised high temperature pad compound, review the car setup or alter your driving style. When exposed to temperatures in excess of 630˚C (Red paint) permanent fatigue and stress concentration is greatly accelerated which may result in premature cracking or warping of the disc rotor. DBA does not warrant disc rotors that have been subjected to motor sport use.

Bulk Temperature is the temperature achieved through the full thickness of the material rather than surface temperatures that may be much higher but have less effect on the mechanical properties of the rotor material.

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[SIGPIC][/SIGPIC]
Should have bought an STI

For the fronts, if you're serious .. You'd want to upgrade to an Alcon or AP Racing kit with bigger rotors, 330 or 370mm.

All depends on what your budgets are, what the plans for the car are .. and find a good bang for buck inbetween.

Have a look here: http://www.rallysportdirect.com/shop...25_28_332.html

Lots of nice things

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[SIGPIC][/SIGPIC]
Should have bought an STI

Im no expert... but your 3000 pads are going to eat rotors!!! thats what they are designed to do!! Hence you had good pedal feel all day and no fade. I would recomend trying some different pads first before going the big brake upgrade$$$.

* Ferrodo DS2500
* Project M
* EBC Green

+1 for the DS2500's with no ABS.
I rekon the Ferodo FS3000 are a bit too excessive with Subaru 4 pots and DBA 4000/5000's.

J

I want to keep the car eligible for targa so that means I have to keep 16" wheels. This sort of restricts what I can use.

As for pads....I am going to go back to the old faithful....Pagid Blues.

Brendon

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Losing is worse than death. You have to live with losing....

Brendon

I'm sure it's the pads mate...I use 5000's but with DS2500.
The 5000's I have on the MY06 are off my old MY02 (albeit different top hats) and have had about 16 months worth of use and are only just starting to get low on the grooves...plus the rotor surface is pretty smooth, unlike yours. Then add in the fact that you drive WAY more aggressively than me.
So there you have it!

Brendon,

My 4000's and 3000 setup looked exactly the same after that day at Collie. The slots on the rotors have actually started filling themselves in with molten rotor material

I'm glad you posted this up because I considered going to 5000's to help remedy the problem, but I see it ends up the same anyway. I have run 2500's in the past but around Waneroo I have noticed they will start to go off. The 3000's stay on song, but yer, I guess the price you pay is a munched rotor or two.

In terms of calipers that fit under the 16's, I know that waaaay back, Duke Ting ran an AP caliper that 'just' squeezed under a 16" - 5 spoke Suby rim. One of the ole' timers on here might know the details.

Alex

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Kiss My RS

good ol dukey!