these are new stock pads!!! they have seen only 2 recent track events and this is what i saw when i checked them out...







look at how one side is worn down, it was the bottom side (leading side) almost as if the bottom piston was pushing and the top was not?? also they chuncked up, is that from heat? the first set of stock pads i had did not do this?

anyone see this before? wow, wtf is all i have to say to this LOL!!! and i have a track event tomorrow....not cool... :=-(

 

You must be getting faster Damian

 

I have a guess..... they're stock pads. They're not built to take that kind of heat. Get some upgraded pads, or vented rotors. But they're definitely not in good shape.

 

Bleed the system dry and check for stuck pucks. Did you hit a curb or anything? That is not right at all, dude.

 

looks like the traling piston inside the caliper is stuck

 

It's those new ss lines damnit!

What we have here is cementite on your discs and failure to bed in the new pads properly. (I have absolutely NO idea but that is some messed up stuff!!) But I sure go with the stuck piston diagnosis.

Read all about it here:

http://www.stoptech.com/whitepapers/...otors_myth.htm

 

you may have a seized piston in you caliper. without pads in have someone push the brakes and watch the pistons move. Then use a pair of large channel locks to reset the pistons and repeat precess to tr to free up the piston. You may need to get new calipers or a rebuild. IMO dont do a rebuild. never as good as new.

 

GT2 seems to have the answer.

If those are "stock" pads and you are doing track events you are working well outside their prescribed temperature range. Additionally, the continued heat has surely boiled your brake fluid and may have caused damage to your calipers. At the minimum, you may have damaged the seals and caused one or more of the pistons (per side) to drag or sieze in their bores.

Another thing: If the calipers are not damaged then you are using way too much pedal pressure and generating too much heat, another sign of the pads being used outside of their heat range.

This is one of the reasons that many race calipers come with differential sized pistons so that at high pedal pressures the pad won't wear unevenly.

Regardless, you need to upgrade to much better brake pads, do a complete flush and fill on brake fluid and pull and rebuild your front calipers.

 

Stock pads don't take track events well. They work really well for the street, not for the track.

Stock rotors are vented...

 

I agree with everone, stock pads + track events, not a good idea. Where all four pads worn like that or just one. If it is just one pad I would go along with the stuck piston idea, if all four, it might just be becasue they are stock pads. Also do you have cross drilled rotors? This could also cause the pads to wear prematurely. Just a thought.

 

I tihk even stock pads would wear evenly, not all lop sided liek that. I'm sideing with the stuck piston theory.

 

man, thanks for all the great replies guys, the rears were fine, but the both sides of the front were liek this, chunked up and worn unevenly, i did work the pistons in and out on each front caliper in hopes to unstick a piston if that was the issue. this was on the original stock rotors.

it was suggested to rebuild the caliper or get a new one, dam is that really what my cource of action should be?

looks like new rotors and pads for me....

 

yeah, im getting a bit faster :-( *wink*

 

I've never seen pads that looked that bad. Damn. I agree with the advise that everyone is giving.....give Hawk HPS or HP+ a try; can't beat the price. How are your rotors looking? Time for some new brake fluid too .

 

You toasted the pads big time. The calipers are probably just fine but at a minimum you need new pads (duh!) and the rotors cleaned up. You didn't notice an issue with the brakes? I would imagine the pads first glazed which you would notice as a decrease in bite and then shortly thereafter if they were further pummeled they would start disintegrating.

The leading edge of the pad always runs hotter and that's why yours look as they do. The pad material actually over heated and failed in a big way.

If you are tracking the car them most important thing you need is a safe car and brakes are important. Don't do it again before making some pad changes.

 

Damian,

my drivers rear looked like that. Long time ago I had "maintenance" done at a mazda dealer...all of a sudden a $200 estimate turned to $2000 as they said my brakes were bad...needless to say they didn't do a good job as the brakes were never right since.

When I had the pads and rotors changed earlier this year, the rx7 mechanic noticed that they must have air screwed the bolts in instead of starting the bolt with by hand tightening. What ended up happening was that he stripped the threads on the caliper side it self...not the bolt. You could tell this when u started to screw the bolt in you could see it "wiggle" instead of staying straight. This caused the brake to not float evenly on the bolt rails....

 

Manute,

I'm really enjoying your new signature. Reminds me of the time I road shotty w/ya through a course.....man, I was like, "where in the hell is he going?? Where's the line? Ohhhhh, my stomach hurts "

Your pal,
Spud

 

Even cheap pads would tend to wear evenly, wouldn't they? It seems that the pads are not being applied even pressure when braking occurs. I agree with those that point the finger at the pistons/caliper problem. Just my .02

 

Look on ebay for the brembo rotors... They are pretty cheap $ wise and work well.

 

once again, thanks for the direction guys, I'll do some more checking and see if a piston is sticking

 

yea for the driving you are doing you need better brakes.

 

My guess is a piston isnt working...

 

well, i kicked some **** at the track saturday and it seemd to hold up with some hawk hps pads that had about 3/4 the pad left on them, ill check the pads today for uneven wear, i moved all the pistons in/out before putting the pads in to make sure none were seized, but made sure i didnt over extend the pistons too

new rotors/pads are planned for the near future, VERY near future, like i am ordering them as i type :-)

 

i can get stock rotors from mazdacomp for really cheap, fronts for $67.45 each and rears for $48.80 each...

and i have herd stock rotors are very good quality from a lot of track drivers

however, pads are a different issue :-)

 

While I don't own an RX7, I just recently did some break work on my 93 eclipse gsx. Mine were worn unevenly much the same yours were because the caliper/piston was siezed and wasn't moving. So it was stuck mostly engaged and was wearing down just one part of the break pad.
The other side of the car had completely worn down the pad so it was just a sliver of metal left. It was a wonderful sound..
Good luck.